diff --git a/src/AllenNeuralDynamics.Zaber/AllenNeuralDynamics.Zaber.csproj b/src/AllenNeuralDynamics.Zaber/AllenNeuralDynamics.Zaber.csproj
index b192a82..3ca057e 100644
--- a/src/AllenNeuralDynamics.Zaber/AllenNeuralDynamics.Zaber.csproj
+++ b/src/AllenNeuralDynamics.Zaber/AllenNeuralDynamics.Zaber.csproj
@@ -9,7 +9,7 @@
     <PackageTags>Bonsai Rx Zaber AllenNeuralDynamics</PackageTags>
     <TargetFramework>net472</TargetFramework>
     <Features>strict</Features>
-    <Version>0.4.2</Version>
+    <Version>0.5.0</Version>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/src/AllenNeuralDynamics.Zaber/GenericCommand.cs b/src/AllenNeuralDynamics.Zaber/GenericCommand.cs
index 53205bc..10e72c2 100644
--- a/src/AllenNeuralDynamics.Zaber/GenericCommand.cs
+++ b/src/AllenNeuralDynamics.Zaber/GenericCommand.cs
@@ -23,7 +23,7 @@ public class GenericCommand : Combinator<string, Response>
         /// Gets or sets the device to be controlled. Defaults to 0.
         /// </summary>
         [Description("The axis index to be actuated.")]
-        public int Device { get; set; } = 0;
+        public int? Device { get; set; }
 
         /// <summary>
         /// Gets or sets the axis of the manipulator to be controlled.
diff --git a/src/AllenNeuralDynamics.Zaber/GenericCommandMultiResponse.cs b/src/AllenNeuralDynamics.Zaber/GenericCommandMultiResponse.cs
index 676f6ac..af226ed 100644
--- a/src/AllenNeuralDynamics.Zaber/GenericCommandMultiResponse.cs
+++ b/src/AllenNeuralDynamics.Zaber/GenericCommandMultiResponse.cs
@@ -24,7 +24,7 @@ public class GenericCommandMultiResponse : Combinator<string, Response[]>
         /// Gets or sets the device to be controlled. Defaults to 0.
         /// </summary>
         [Description("The axis index to be actuated.")]
-        public int Device { get; set; } = 0;
+        public int? Device { get; set; }
 
         /// <summary>
         /// Gets or sets the axis of the manipulator to be controlled.
diff --git a/src/AllenNeuralDynamics.Zaber/GenericCommandNoResponse.cs b/src/AllenNeuralDynamics.Zaber/GenericCommandNoResponse.cs
index 87749e9..a0a1fdc 100644
--- a/src/AllenNeuralDynamics.Zaber/GenericCommandNoResponse.cs
+++ b/src/AllenNeuralDynamics.Zaber/GenericCommandNoResponse.cs
@@ -24,7 +24,7 @@ public class GenericCommandNoResponse : Sink<string>
         /// Gets or sets the device to be controlled. Defaults to 0.
         /// </summary>
         [Description("The axis index to be actuated.")]
-        public int Device { get; set; } = 0;
+        public int? Device { get; set; }
 
         /// <summary>
         /// Gets or sets the axis of the manipulator to be controlled.
diff --git a/src/AllenNeuralDynamics.Zaber/ZaberDevice.cs b/src/AllenNeuralDynamics.Zaber/ZaberDevice.cs
index c239a79..f8deede 100644
--- a/src/AllenNeuralDynamics.Zaber/ZaberDevice.cs
+++ b/src/AllenNeuralDynamics.Zaber/ZaberDevice.cs
@@ -89,8 +89,9 @@ public void Home(int? deviceIndex, int? axis)
 
         public void GenericCommandNoResponse(int? deviceIndex, int? axis, string command)
         {
-            var device = devices[deviceIndex.HasValue ? deviceIndex.Value : 0];
-            device.GenericCommandNoResponseAsync(command, axis.HasValue? axis.Value : 0);
+            comm.GenericCommandNoResponseAsync(command,
+                deviceIndex.HasValue ? deviceIndex.Value : 0,
+                axis.HasValue? axis.Value : 0);
         }
 
         public async Task<double> GetPosition(int? deviceIndex, int axis, Units unit)
@@ -127,14 +128,18 @@ public async Task<Unit> WaitUntilIdle(int? deviceIndex, int? axis)
 
         public async Task<Response[]> GenericCommandMultiResponse(int? deviceIndex, int? axis, string command)
         {
-            var device = devices[deviceIndex.HasValue ? deviceIndex.Value : 0];
-            return await device.GenericCommandMultiResponseAsync(command, axis.HasValue? axis.Value : 0);
+                return await comm.GenericCommandMultiResponseAsync(
+                    command,
+                    deviceIndex.HasValue ? deviceIndex.Value : 0,
+                    axis.HasValue ? axis.Value : 0);
         }
 
         public async Task<Response> GenericCommand(int? deviceIndex, int? axis, string command)
         {
-            var device = devices[deviceIndex.HasValue ? deviceIndex.Value : 0];
-            return await device.GenericCommandAsync(command, axis.HasValue ? axis.Value : 0);
+            return await comm.GenericCommandAsync(
+                command,
+                deviceIndex.HasValue ? deviceIndex.Value : 0,
+                axis.HasValue ? axis.Value : 0);
         }
 
         /// <summary>