It's a small, yet heavyweight alternative bass drum mic holder. You could install Kelly Shu, but instead you can get a proper metal holder at lower price than competitors plastic version. You need to use two screws from lug in order to put it in the position. Ensure you have enough long screws for holder plate - thicker than typical washer (especially when you install it inside vintage drum, such as Gretsch). It holds steady in the installed position, but you have to strongly tighten it's bolts. It is little tricky and unhandy to do, especially when holder is already mounted inside bass drum. Holder saves space and need to take additional mount. Very handy solution for gigging drummer.