diff --git a/acsApp/src/devAcsMotor.dbd b/acsApp/src/devAcsMotor.dbd
index 061fd61..1764a62 100644
--- a/acsApp/src/devAcsMotor.dbd
+++ b/acsApp/src/devAcsMotor.dbd
@@ -1,6 +1,11 @@
 # Advanced Control Systems driver support.
+
+# Model 1 (non-asyn) driver
 device(motor,VME_IO,devMCB4B,"ACS MCB-4B")
 driver(drvMCB4B)
 registrar(AcsRegister)
 
+# Model 3 driver
+registrar(MCB4BRegister)
+