diff --git a/board/czechlight/clearfog/sdn-inline-clearfog.dts b/board/czechlight/clearfog/sdn-inline-clearfog.dts
index 2e9e648..9787d4c 100644
--- a/board/czechlight/clearfog/sdn-inline-clearfog.dts
+++ b/board/czechlight/clearfog/sdn-inline-clearfog.dts
@@ -1,3 +1,4 @@
+#define CLEARFOG_REV1
 #include "sdn-roadm-clearfog.dtsi"
 #include "clearfog-output-voa.dtsi"