diff --git a/include/DiscreteAngle.h b/include/DiscreteAngle.h
index ee2ca31..d5e0c95 100644
--- a/include/DiscreteAngle.h
+++ b/include/DiscreteAngle.h
@@ -4,7 +4,7 @@
 #include "Range.h"
 
 // A fixed point 16-bit signed angle between (-180..180]
-class DiscreteAngle16 : Range16 {
+class DiscreteAngle16 : public Range16 {
 public:
   DiscreteAngle16(float angle);
 };