diff --git a/include/apple2.h b/include/apple2.h
index 421b5db6c..31e56a95a 100644
--- a/include/apple2.h
+++ b/include/apple2.h
@@ -134,6 +134,7 @@ extern unsigned char _dos_type;
 ** ProDOS 8 2.0.1 - 0x21
 ** ProDOS 8 2.0.2 - 0x22
 ** ProDOS 8 2.0.3 - 0x23
+** ProDOS 8 2.4.x - 0x24
 */