You know, I have never heard of this "solvent trap" and I had to do some Googling. I actually really like the idea and would even pay the stupid 35 bucks for one as I think this would be great for cleaning my m&p 15r after shooting corrosive 5.45x39. I like the idea of being able to clean it without having to take it outside and running all the salts, carbon, chemicals into the ground. That said, I am hesitant to order it from these guys as I don't want to end up on some list when the ATF decides these are NFA items.Well if your okay with illegally manufacturing silencers you may as well buy their unserialized "solvent trap" and call it a day.