diff --git a/scale/src/main/java/com/strategyobject/substrateclient/scale/ScaleType.java b/scale/src/main/java/com/strategyobject/substrateclient/scale/ScaleType.java
index 98d3d28e..3f7ff5a6 100644
--- a/scale/src/main/java/com/strategyobject/substrateclient/scale/ScaleType.java
+++ b/scale/src/main/java/com/strategyobject/substrateclient/scale/ScaleType.java
@@ -93,4 +93,7 @@ class Union11<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11> implements ScaleType
 
     class Union12<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12> implements ScaleType {
     }
+
+    class Pair<F, S> implements ScaleType {
+    }
 }
diff --git a/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleReaderRegistry.java b/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleReaderRegistry.java
index fa60d64f..3cdbb115 100644
--- a/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleReaderRegistry.java
+++ b/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleReaderRegistry.java
@@ -59,7 +59,7 @@ public ScaleReaderRegistry() {
         register(new Union10Reader(), Union10.class, ScaleType.Union10.class);
         register(new Union11Reader(), Union11.class, ScaleType.Union11.class);
         register(new Union12Reader(), Union12.class, ScaleType.Union12.class);
-        register(new PairReader(), Pair.class);
+        register(new PairReader(), Pair.class, ScaleType.Pair.class);
         register(new VecReader(), ScaleType.Vec.class, List.class);
         register(new ArrayReader(), Array.class);
         register(new BooleanArrayReader(), boolean[].class);
diff --git a/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleWriterRegistry.java b/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleWriterRegistry.java
index 4af023b2..a28e8797 100644
--- a/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleWriterRegistry.java
+++ b/scale/src/main/java/com/strategyobject/substrateclient/scale/registries/ScaleWriterRegistry.java
@@ -60,7 +60,7 @@ public ScaleWriterRegistry() {
         register(new Union10Writer(), Union10.class, ScaleType.Union10.class);
         register(new Union11Writer(), Union11.class, ScaleType.Union11.class);
         register(new Union12Writer(), Union12.class, ScaleType.Union12.class);
-        register(new PairWriter(), Pair.class);
+        register(new PairWriter(), Pair.class, ScaleType.Pair.class);
         register(new VecWriter(), ScaleType.Vec.class, List.class);
         register(new HeterogeneousVecWriter(this), ScaleType.HeterogeneousVec.class, HeterogeneousVecWriter.HeterogeneousVec.class);
         register(new ArrayWriter(), Array.class);