Beyond designed to adapt an oil filter to a gun, as if that weren't enough, also actively marketed as a silencer.
I'd bet $10 to a donut that the majority of purchasers are using these things as illegal silencers. (Before one of those purchasers gets all up in arms that I'm accusing them individually and specifically, if you're offended I'm not talking about you. You're in the other group.)
I simply can not conceive of spending $75 for a "solvent trap " when there are so many other suitable and far less expensive options available. It's not as if they're $5 or $10 cheaper either, we're talking $50-$65 cheaper, besides the fact that the vast majority of gun owners don't use a "solvent trap" at all.