diff --git a/Content.Client/Chemistry/UI/ChemMasterBoundUserInterface.cs b/Content.Client/Chemistry/UI/ChemMasterBoundUserInterface.cs
index dcff475c3a..f6b494869a 100644
--- a/Content.Client/Chemistry/UI/ChemMasterBoundUserInterface.cs
+++ b/Content.Client/Chemistry/UI/ChemMasterBoundUserInterface.cs
@@ -44,6 +44,10 @@ namespace Content.Client.Chemistry.UI
                     (uint) _window.BottleDosage.Value, _window.LabelLine));
             _window.BufferSortButton.OnPressed += _ => SendMessage(
                     new ChemMasterSortingTypeCycleMessage());
+            _window.OutputBufferDraw.OnPressed += _ => SendMessage(
+                new ChemMasterOutputDrawSourceMessage(ChemMasterDrawSource.Internal));
+            _window.OutputBeakerDraw.OnPressed += _ => SendMessage(
+                new ChemMasterOutputDrawSourceMessage(ChemMasterDrawSource.External));
 
             for (uint i = 0; i < _window.PillTypeButtons.Length; i++)
             {
diff --git a/Content.Client/Chemistry/UI/ChemMasterWindow.xaml b/Content.Client/Chemistry/UI/ChemMasterWindow.xaml
index 0fe7daff36..23d730cefa 100644
--- a/Content.Client/Chemistry/UI/ChemMasterWindow.xaml
+++ b/Content.Client/Chemistry/UI/ChemMasterWindow.xaml
@@ -83,10 +83,13 @@
 
             <!-- Packaging -->
             <BoxContainer Orientation="Horizontal">
-                <Label Text="{Loc 'chem-master-window-packaging-text'}" />
+                <Label Text="{Loc 'chem-master-output-source'}" StyleClasses="LabelSecondaryColor" Margin="0 0 5 0"/>
+                <Button MinSize="80 0" Name="OutputBufferDraw" Access="Public" Text="{Loc 'chem-master-output-buffer-draw'}" ToggleMode="True" StyleClasses="OpenRight" />
+                <Button MinSize="80 0" Name="OutputBeakerDraw" Access="Public" Text="{Loc 'chem-master-output-beaker-draw'}" ToggleMode="True" StyleClasses="OpenLeft" />
                 <Control HorizontalExpand="True"/>
-                <Label Text="{Loc 'chem-master-window-container-label'}" /> <!-- DeltaV-->
-                <Label Name="BufferCurrentVolume" StyleClasses="LabelWeak" />
+                <!-- Output Draw Source -->
+                <Label Name="DrawSource"/>
+                <Label Name="BufferCurrentVolume" StyleClasses="LabelSecondaryColor" />
             </BoxContainer>
 
             <!-- Wrap the packaging info-->
diff --git a/Content.Client/Chemistry/UI/ChemMasterWindow.xaml.cs b/Content.Client/Chemistry/UI/ChemMasterWindow.xaml.cs
index c9353485b8..2152a0be1c 100644
--- a/Content.Client/Chemistry/UI/ChemMasterWindow.xaml.cs
+++ b/Content.Client/Chemistry/UI/ChemMasterWindow.xaml.cs
@@ -150,7 +150,17 @@ namespace Content.Client.Chemistry.UI
             // Ensure the Panel Info is updated, including UI elements for Buffer Volume, Output Container and so on
             UpdatePanelInfo(castState);
 
-            BufferCurrentVolume.Text = $" {castState.InputContainerInfo?.CurrentVolume.Int() ?? 0}u"; // DeltaV
+            switch (castState.DrawSource)
+            {
+                case ChemMasterDrawSource.Internal:
+                    SetBufferText(castState.BufferCurrentVolume, "chem-master-output-buffer-draw");
+                    break;
+                case ChemMasterDrawSource.External:
+                    SetBufferText(castState.InputContainerInfo?.CurrentVolume, "chem-master-output-beaker-draw");
+                    break;
+                default:
+                    throw new($"Chemmaster {castState.OutputContainerInfo} draw source is not set");
+            }
 
             InputEjectButton.Disabled = castState.InputContainerInfo is null;
             OutputEjectButton.Disabled = castState.OutputContainerInfo is null;
@@ -168,9 +178,14 @@ namespace Content.Client.Chemistry.UI
             var holdsReagents = output?.Reagents != null;
             var pillNumberMax = holdsReagents ? 0 : remainingCapacity;
             var bottleAmountMax = holdsReagents ? remainingCapacity : 0;
-            var bufferVolume = castState.BufferCurrentVolume?.Int() ?? 0;
+            var outputVolume = castState.DrawSource switch
+            {
+                ChemMasterDrawSource.Internal => castState.BufferCurrentVolume?.Int() ?? 0,
+                ChemMasterDrawSource.External => castState.InputContainerInfo?.CurrentVolume.Int() ?? 0,
+                _ => 0,
+            };
 
-            PillDosage.Value = (int)Math.Min(bufferVolume, castState.PillDosageLimit);
+            PillDosage.Value = (int)Math.Min(outputVolume, castState.PillDosageLimit);
 
             PillTypeButtons[castState.SelectedPillType].Pressed = true;
 
@@ -186,25 +201,35 @@ namespace Content.Client.Chemistry.UI
             // Avoid division by zero
             if (PillDosage.Value > 0)
             {
-                PillNumber.Value = Math.Min(bufferVolume / PillDosage.Value, pillNumberMax);
+                PillNumber.Value = Math.Min(outputVolume / PillDosage.Value, pillNumberMax);
             }
             else
             {
                 PillNumber.Value = 0;
             }
 
-            BottleDosage.Value = Math.Min(bottleAmountMax, bufferVolume);
+            BottleDosage.Value = Math.Min(bottleAmountMax, outputVolume);
         }
         /// <summary>
-        /// Generate a product label based on reagents in the buffer.
+        /// Generate a product label based on reagents in the buffer or beaker.
         /// </summary>
         /// <param name="state">State data sent by the server.</param>
         private string GenerateLabel(ChemMasterBoundUserInterfaceState state)
         {
-            if (state.BufferCurrentVolume == 0)
+            if (
+                state.BufferCurrentVolume == 0 && state.DrawSource == ChemMasterDrawSource.Internal ||
+                state.InputContainerInfo?.CurrentVolume == 0 && state.DrawSource == ChemMasterDrawSource.External ||
+                state.InputContainerInfo?.Reagents == null
+            )
                 return "";
 
-            var reagent = state.BufferReagents.OrderBy(r => r.Quantity).First().Reagent;
+            var reagent = (state.DrawSource switch
+                {
+                    ChemMasterDrawSource.Internal => state.BufferReagents,
+                    ChemMasterDrawSource.External => state.InputContainerInfo.Reagents ?? [],
+                    _ => throw new($"Chemmaster {state.OutputContainerInfo} draw source is not set"),
+                }).MinBy(r => r.Quantity)
+                .Reagent;
             _prototypeManager.TryIndex(reagent.Prototype, out ReagentPrototype? proto);
             return proto?.LocalizedName ?? "";
         }
@@ -230,6 +255,8 @@ namespace Content.Client.Chemistry.UI
                 _ => Loc.GetString("chem-master-window-sort-type-none")
             };
 
+            OutputBufferDraw.Pressed = state.DrawSource == ChemMasterDrawSource.Internal;
+            OutputBeakerDraw.Pressed = state.DrawSource == ChemMasterDrawSource.External;
 
             if (!state.BufferReagents.Any())
             {
@@ -411,6 +438,12 @@ namespace Content.Client.Chemistry.UI
             get => LabelLineEdit.Text;
             set => LabelLineEdit.Text = value;
         }
+
+        private void SetBufferText(FixedPoint2? volume, string text)
+        {
+            BufferCurrentVolume.Text = $" {volume ?? FixedPoint2.Zero}u";
+            DrawSource.Text = Loc.GetString(text);
+        }
     }
 
     public sealed class ReagentButton : Button
diff --git a/Content.Server/Chemistry/Components/ChemMasterComponent.cs b/Content.Server/Chemistry/Components/ChemMasterComponent.cs
index 80e3752a86..fe5b14a8ce 100644
--- a/Content.Server/Chemistry/Components/ChemMasterComponent.cs
+++ b/Content.Server/Chemistry/Components/ChemMasterComponent.cs
@@ -27,5 +27,11 @@ namespace Content.Server.Chemistry.Components
 
         [DataField("clickSound"), ViewVariables(VVAccess.ReadWrite)]
         public SoundSpecifier ClickSound = new SoundPathSpecifier("/Audio/Machines/machine_switch.ogg");
+
+        /// <summary>
+        /// Which source the chem master should draw from when making pills/bottles.
+        /// </summary>
+        [DataField]
+        public ChemMasterDrawSource DrawSource = ChemMasterDrawSource.Internal;
     }
 }
diff --git a/Content.Server/Chemistry/EntitySystems/ChemMasterSystem.cs b/Content.Server/Chemistry/EntitySystems/ChemMasterSystem.cs
index 35cb6ebe6f..51dc436486 100644
--- a/Content.Server/Chemistry/EntitySystems/ChemMasterSystem.cs
+++ b/Content.Server/Chemistry/EntitySystems/ChemMasterSystem.cs
@@ -57,6 +57,7 @@ namespace Content.Server.Chemistry.EntitySystems
             SubscribeLocalEvent<ChemMasterComponent, ChemMasterReagentAmountButtonMessage>(OnReagentButtonMessage);
             SubscribeLocalEvent<ChemMasterComponent, ChemMasterCreatePillsMessage>(OnCreatePillsMessage);
             SubscribeLocalEvent<ChemMasterComponent, ChemMasterOutputToBottleMessage>(OnOutputToBottleMessage);
+            SubscribeLocalEvent<ChemMasterComponent, ChemMasterOutputDrawSourceMessage>(OnSetDrawSourceMessage);
         }
 
         private void SubscribeUpdateUiState<T>(Entity<ChemMasterComponent> ent, ref T ev)
@@ -76,8 +77,8 @@ namespace Content.Server.Chemistry.EntitySystems
             var bufferCurrentVolume = bufferSolution.Volume;
 
             var state = new ChemMasterBoundUserInterfaceState(
-                chemMaster.SortingType, BuildInputContainerInfo(inputContainer), BuildOutputContainerInfo(outputContainer), // DeltaV - removed mode
-                bufferReagents, bufferCurrentVolume, chemMaster.PillType, chemMaster.PillDosageLimit, updateLabel);
+                /*chemMaster.Mode,*/ chemMaster.SortingType, BuildInputContainerInfo(inputContainer), BuildOutputContainerInfo(outputContainer), // DeltaV - Removed discarding
+                bufferReagents, bufferCurrentVolume, chemMaster.PillType, chemMaster.PillDosageLimit, updateLabel, chemMaster.DrawSource);
 
             _userInterfaceSystem.SetUiState(owner, ChemMasterUiKey.Key, state);
         }
@@ -124,6 +125,17 @@ namespace Content.Server.Chemistry.EntitySystems
             ClickSound(chemMaster);
         }
 
+        private void OnSetDrawSourceMessage(Entity<ChemMasterComponent> chemMaster, ref ChemMasterOutputDrawSourceMessage message)
+        {
+            //Ensure draw source is valid, either from the internal buffer or the inserted beaker
+            if (!Enum.IsDefined(message.DrawSource))
+                return;
+
+            chemMaster.Comp.DrawSource = message.DrawSource;
+            UpdateUiState(chemMaster);
+            ClickSound(chemMaster);
+        }
+
         private void TransferReagents(Entity<ChemMasterComponent> chemMaster, ReagentId id, FixedPoint2 amount, bool fromBuffer)
         {
             var container = _itemSlotsSystem.GetItemOrNull(chemMaster, SharedChemMaster.InputSlotName);
@@ -173,9 +185,9 @@ namespace Content.Server.Chemistry.EntitySystems
                 return;
 
             var needed = message.Dosage * message.Number;
-            if (!WithdrawFromBuffer(chemMaster, needed, user, out var withdrawal))
-                return;
 
+            if (!WithdrawFromSource(chemMaster, needed, user, out var withdrawal))
+                return;
             _labelSystem.Label(container, message.Label);
 
             for (var i = 0; i < message.Number; i++)
@@ -184,7 +196,10 @@ namespace Content.Server.Chemistry.EntitySystems
                 _storageSystem.Insert(container, item, out _, user: user, storage);
                 _labelSystem.Label(item, message.Label);
 
-                _solutionContainerSystem.EnsureSolutionEntity(item, SharedChemMaster.PillSolutionName,out var itemSolution ,message.Dosage);
+                _solutionContainerSystem.EnsureSolutionEntity(item,
+                    SharedChemMaster.PillSolutionName,
+                    out var itemSolution,
+                    message.Dosage);
                 if (!itemSolution.HasValue)
                     return;
 
@@ -221,7 +236,7 @@ namespace Content.Server.Chemistry.EntitySystems
             if (message.Label.Length > SharedChemMaster.LabelMaxLength)
                 return;
 
-            if (!WithdrawFromBuffer(chemMaster, message.Dosage, user, out var withdrawal))
+            if (!WithdrawFromSource(chemMaster, message.Dosage, user, out var withdrawal))
                 return;
 
             _labelSystem.Label(container, message.Label);
@@ -235,45 +250,77 @@ namespace Content.Server.Chemistry.EntitySystems
             ClickSound(chemMaster);
         }
 
-        private bool WithdrawFromBuffer(
+        private bool WithdrawFromSource(
             Entity<ChemMasterComponent> chemMaster,
-            FixedPoint2 neededVolume, EntityUid? user,
+            FixedPoint2 neededVolume,
+            EntityUid? user,
             [NotNullWhen(returnValue: true)] out Solution? outputSolution)
         {
             outputSolution = null;
 
-            /* DeltaV - use beaker slot instead of buffer
-            if (!_solutionContainerSystem.TryGetSolution(chemMaster.Owner, SharedChemMaster.BufferSolutionName, out _, out var solution))
-            {
-                return false;
-            }
-            */
-            // Begin DeltaV Additions - Use beaker slot instead of buffer
-            var container = _itemSlotsSystem.GetItemOrNull(chemMaster, SharedChemMaster.InputSlotName);
-            if (container is null ||
-                !_solutionContainerSystem.TryGetFitsInDispenser(container.Value, out var containerSoln, out var solution))
-            {
-                return false;
-            }
-            // End DeltaV Additions
+            Solution? solution;
+            Entity<SolutionComponent>? soln = null;
 
-            if (solution.Volume == 0)
+            switch (chemMaster.Comp.DrawSource)
             {
-                if (user.HasValue)
-                    _popupSystem.PopupCursor(Loc.GetString("chem-master-window-buffer-empty-text"), user.Value);
-                return false;
-            }
+                case ChemMasterDrawSource.Internal:
+                    if (!_solutionContainerSystem.TryGetSolution(chemMaster.Owner, SharedChemMaster.BufferSolutionName, out _, out solution))
+                        return false;
 
-            // ReSharper disable once InvertIf
-            if (neededVolume > solution.Volume)
-            {
-                if (user.HasValue)
-                    _popupSystem.PopupCursor(Loc.GetString("chem-master-window-buffer-low-text"), user.Value);
-                return false;
+                    if (solution.Volume == 0)
+                    {
+                        if (user is { } uid)
+                            _popupSystem.PopupCursor(Loc.GetString("chem-master-window-buffer-empty-text"), uid);
+
+                        return false;
+                    }
+                    if (neededVolume > solution.Volume)
+                    {
+                        if (user is { } uid)
+                            _popupSystem.PopupCursor(Loc.GetString("chem-master-window-buffer-low-text"), uid);
+
+                        return false;
+                    }
+
+                    break;
+
+                case ChemMasterDrawSource.External:
+                    if (_itemSlotsSystem.GetItemOrNull(chemMaster, SharedChemMaster.InputSlotName) is not {} container)
+                    {
+                        if (user.HasValue)
+                            _popupSystem.PopupCursor(Loc.GetString("chem-master-window-no-beaker-text"), user.Value);
+                        return false;
+                    }
+
+                    if (!_solutionContainerSystem.TryGetFitsInDispenser(container, out soln, out solution))
+                        return false;
+
+                    if (solution.Volume == 0)
+                    {
+                        if (user is { } uid)
+                            _popupSystem.PopupCursor(Loc.GetString("chem-master-window-beaker-empty-text"), uid);
+
+                        return false;
+                    }
+                    if (neededVolume > solution.Volume)
+                    {
+                        if (user is { } uid)
+                            _popupSystem.PopupCursor(Loc.GetString("chem-master-window-beaker-low-text"), uid);
+
+                        return false;
+                    }
+
+                    break;
+
+                default:
+                    return false;
             }
 
             outputSolution = solution.SplitSolution(neededVolume);
-            _solutionContainerSystem.UpdateChemicals(containerSoln.Value); // DeltaV
+
+            if (soln.HasValue)
+                _solutionContainerSystem.UpdateChemicals(soln.Value);
+
             return true;
         }
 
diff --git a/Content.Shared/Chemistry/SharedChemMaster.cs b/Content.Shared/Chemistry/SharedChemMaster.cs
index 3afeac003d..f95f2a4860 100644
--- a/Content.Shared/Chemistry/SharedChemMaster.cs
+++ b/Content.Shared/Chemistry/SharedChemMaster.cs
@@ -72,6 +72,12 @@ namespace Content.Shared.Chemistry
         }
     }
 
+    [Serializable, NetSerializable]
+    public sealed class ChemMasterOutputDrawSourceMessage(ChemMasterDrawSource drawSource) : BoundUserInterfaceMessage
+    {
+        public readonly ChemMasterDrawSource DrawSource = drawSource;
+    }
+
     /* DeltaV - removed discarding
     public enum ChemMasterMode
     {
@@ -105,6 +111,12 @@ namespace Content.Shared.Chemistry
         All,
     }
 
+    public enum ChemMasterDrawSource
+    {
+        Internal,
+        External,
+    }
+
     public static class ChemMasterReagentAmountToFixedPoint
     {
         public static FixedPoint2 GetFixedPoint(this ChemMasterReagentAmount amount)
@@ -174,11 +186,13 @@ namespace Content.Shared.Chemistry
 
         public readonly bool UpdateLabel;
 
+        public readonly ChemMasterDrawSource DrawSource;
+
         public ChemMasterBoundUserInterfaceState(
             // DeltaV - removed discarding
             ChemMasterSortingType sortingType, ContainerInfo? inputContainerInfo, ContainerInfo? outputContainerInfo,
             IReadOnlyList<ReagentQuantity> bufferReagents, FixedPoint2 bufferCurrentVolume,
-            uint selectedPillType, uint pillDosageLimit, bool updateLabel)
+            uint selectedPillType, uint pillDosageLimit, bool updateLabel, ChemMasterDrawSource drawSource)
         {
             InputContainerInfo = inputContainerInfo;
             OutputContainerInfo = outputContainerInfo;
@@ -189,6 +203,7 @@ namespace Content.Shared.Chemistry
             SelectedPillType = selectedPillType;
             PillDosageLimit = pillDosageLimit;
             UpdateLabel = updateLabel;
+            DrawSource = drawSource;
         }
     }
 
diff --git a/Resources/Locale/en-US/chemistry/components/chem-master-component.ftl b/Resources/Locale/en-US/chemistry/components/chem-master-component.ftl
index 6f2e9b1d38..d01f3f7480 100644
--- a/Resources/Locale/en-US/chemistry/components/chem-master-component.ftl
+++ b/Resources/Locale/en-US/chemistry/components/chem-master-component.ftl
@@ -31,3 +31,10 @@ chem-master-window-sort-type-none = Sort by: Oldest First
 chem-master-window-sort-type-alphabetical = Sort by: Alphabetical
 chem-master-window-sort-type-quantity = Sort by: Quantity
 chem-master-window-sort-type-latest = Sort by: Recent First
+chem-master-output-buffer-draw = Buffer
+chem-master-output-beaker-draw = Beaker
+chem-master-window-no-beaker-text = No beaker loaded
+chem-master-window-beaker-empty-text = Beaker Empty
+chem-master-window-beaker-low-text = Not enough solution in beaker
+chem-master-output-source = Packaging source:
+chem-master-no-source = No Source