diff --git a/OpenNest.Core/CNC/SubProgramCall.cs b/OpenNest.Core/CNC/SubProgramCall.cs
index 0c9223a..647ac44 100644
--- a/OpenNest.Core/CNC/SubProgramCall.cs
+++ b/OpenNest.Core/CNC/SubProgramCall.cs
@@ -1,4 +1,5 @@
-using OpenNest.Geometry;
+using System.Text;
+using OpenNest.Geometry;
 using OpenNest.Math;
 
 namespace OpenNest.CNC
@@ -90,9 +91,13 @@ namespace OpenNest.CNC
 
         public override string ToString()
         {
+            var sb = new StringBuilder();
+            sb.Append($"G65 P{Id}");
             if (Offset.X != 0 || Offset.Y != 0)
-                return string.Format("G65 P{0} X{1} Y{2}", Id, Offset.X, Offset.Y);
-            return string.Format("G65 P{0} R{1}", Id, Rotation);
+                sb.Append($" X{Offset.X} Y{Offset.Y}");
+            if (Rotation != 0)
+                sb.Append($" R{Rotation}");
+            return sb.ToString();
         }
     }
 }
diff --git a/OpenNest.Tests/CuttingStrategy/HoleSubProgramTests.cs b/OpenNest.Tests/CuttingStrategy/HoleSubProgramTests.cs
index 6ade4cd..abeefb7 100644
--- a/OpenNest.Tests/CuttingStrategy/HoleSubProgramTests.cs
+++ b/OpenNest.Tests/CuttingStrategy/HoleSubProgramTests.cs
@@ -44,6 +44,25 @@ public class HoleSubProgramTests
         Assert.Contains("Y2.5", str);
     }
 
+    [Fact]
+    public void SubProgramCall_ToString_IncludesOffsetAndRotation()
+    {
+        var call = new SubProgramCall { Id = 1000, Offset = new Vector(1.5, 2.5), Rotation = 30 };
+        var str = call.ToString();
+        Assert.Contains("P1000", str);
+        Assert.Contains("X1.5", str);
+        Assert.Contains("Y2.5", str);
+        Assert.Contains("R30", str);
+    }
+
+    [Fact]
+    public void SubProgramCall_ToString_OmitsZeroFields()
+    {
+        var call = new SubProgramCall { Id = 1000 };
+        var str = call.ToString();
+        Assert.Equal("G65 P1000", str);
+    }
+
     [Fact]
     public void Program_SubPrograms_EmptyByDefault()
     {