Awful hop up. I got this for my XCR with a 130 spring and I had feeding issues and it could not put enough backspin on the bb's, plus they were flying all over the place. I ended up putting the stock echo 1 hop up back in and it worked a million times better (actual calculation).
-it's red, which is cool, I guess
-my wallet was lighter
-significantly decreases range
so basically all the things an upgraded hop up is supposed to do, this thing does the exact opposite.