MS1233 Bosch Crown Stops Kit for Miter Saws allows crown molding to be nested against fence for simple miter cuts with no beveling required. When not in use MS1233 Bosch Crown Stops Kit for Miter Saws can be easily flipped back over the fence and stored on the tool out of the way of other cutting applications. MS1233 Bosch Crown Stops Kit for Miter Saws works will models: GCM12SD CM10GD CM12 CM8S CM12SD 5412 4410 4405 4310 and 4212. Does NOT work with models 5312 4412 3912 or 3915.