Yes, the trigger box was around $30. I have an aluminum piston and an m170 spring. However I'm learning that it might possibly be the o-ring but I'm baffled by the fact such a small part could have a huge impact on performance. Mgunner, what part should I teflon tape? I have a PDI hopup and I've heard of guys taping their stock hopup units to decrease air leaks. Could my hop up be leaking possibly? I just bought it along with a repair kit for it. But like I said, most claim it to be the oring on the piston.