This product is manufactured by FIRST STRIKE.
I run this on my FS T15, using a deadlywind barrel with freak inserts. This turns what is a great marker even with the stock barrel, into something awesomely accurate when shooting just reg paint. Shooting First Strike? throw a rifled barrel on and you're in heaven. This adapter allows you to do so much more, opens up a lot of options. Few friends who own T15 were skeptical, and stuck to stock barrels. The fear of "too many parts" or "barrel unthreading from adapter". I haven't had any problems with it unscrewing from the barrel and having the adapter stuck in the receiver.