Drove 3 hours to a shop that did prints, photo's, everything. One stop shopping, they showed me the video of the dirty 30 and pulled one out of the case, small well built inexpensive. So since I'm there might as well buy 2. 9 months later drove 3 hrs picked them up and came home. On my 22" barreled 221 fire ball you need ear protection. On my 300 B.O. AR with standard velocity rounds you should have ear protection. If you are out on the open prairie they are not awful, but if shooting with any surface to echo off of they make a lot of noise. The ad says it will make your B.O. sound like a gaseous emission, I called them on it, and was told that only happens with sub sonic load.
Should have stuck with Thunder beasts, but was looking for a permanent can for the B.O. and a seasonal one for the fire ball.