diff --git a/LEGO1/mxatomidcounter.cpp b/LEGO1/mxatomidcounter.cpp
index 7090c76f..a38dbe6f 100644
--- a/LEGO1/mxatomidcounter.cpp
+++ b/LEGO1/mxatomidcounter.cpp
@@ -1,4 +1,8 @@
 #include "mxatomidcounter.h"
+#include "decomp.h"
+
+DECOMP_SIZE_ASSERT(MxAtomIdCounter, 0x14);
+DECOMP_SIZE_ASSERT(MxAtomIdCounterSet, 0x10);
 
 // OFFSET: LEGO1 0x100ad7f0
 void MxAtomIdCounter::Inc()