This is a plastics bracket for moded razors. If you don't have the stock battery cover on, the plastics are floppy and shake in the wind. This helps keep the ridged and looking sweet. Put a dab of glue in the hole to hold the plastics to the bracket and bolt the other side the batter cover hole on the frame. It looks good and functions well. It fits the SX 500 and I would assume it works on the mx series as well, but i don't have one to test it on, so comment if it works and ill update the description.