This is one of the most ingenious products we've seen for scenario paintball and airsoft yet! This foregrip fits to any Weaver or Picatiny tactical rail providing a large and secure grip. When you want to take that steady sniper shot you simply push a button and bipod legs spring out from the bottom ! They retract with ease as well. Fits BT-4, Tippmann X7 and any other marker or accessory with a tactical rail.