Sorry for the weird question but a while back I purchased some matech sights that I assumed were takeoffs from some Colt rifles. They look like my legit ones, save for one detail. On my known legit Matechs the mounting screw has red threadlocker, while these have yellow (like what Magpul uses). Looking at pictures online I've noticed the majority have red as well. Now I'm worried I have a couple knockoffs. Has anybody ever encountered a matech like that? Thanks.