cowcow glock 17 gen 4 hop up kammerCowCow has made an upgraded hop up chamber for the Glock 17 Gen 4 from TM. It is made of 7075 aluminum and is CNC cut. It is also made in a lightweight design so it doesn't weigh much. It gives better consistency on the shot end and increases your precision. This gives you really sharp durability! It has been redesigned from the "normal" standard and provides extra support for the lower part of the chamber.