I initially purchased this to go over my orange plastic flash hider on my Echo-1 AR-57 so I didn't have to mess around with removing it. The suppressor has a nice finish on the outside and is actually very light, the inside is filled with foam and it did actually change the sound of my gun a little. The bottom unscrews to fit over the flash hider and is then tightened to secure itself in place. If this happens to fit loosely on your flash hider, just put some electrical tape around the base of the flash hider (this is what I did and now the suppressor is very secure, this also stopped bb's from hitting the end of it and shattering). Note: Do NOT unscrew the bottom portion all of the way, as it will come off and the little ball bearings will fall out.

It is ballbearing not threads