Outer Circlip - Pits! The snap ring groove is a quarter of the way it should be, allowing the snap ring to "pop outโ and break the block. Facts didn't support this, but at first I thought I might be over rated capacity using the bucking block in my four wheel snow thrower. However, I did NOT exceed the rated load, and there were NO factors causing failure other than poor design! the pin that the roller rides on and the roller that lies on the ground. No damage, just a design flaw! A simple case