This Heckler & Koch HK MP7 Lower Power Bolt is designed for airsoft gamers who engage in close quarter battle. Reducing the power in just about anything, whether it's your car, guns, or stereo system, seems counterintuitive and borderline absurd at times. However, there are times when it is necessary to "dial it down." Close quarter battles, particularly those airsoft games played indoors where maximum gun velocities are limited to 350 FPS with a .20g BB are the primary reason one might be in need of the HK MP7 Low Power Bolt. Elite Force Airsoft and Umarex Airguns offer the HK MP7 Low Power Bolt as an option to allow HK MP7 GBB (KWA version) users the ability to replace their MP7's standard bolt in order to comply with indoor field velocity limits. Easy to install, hard to play without it. Licensed Trademark of Heckler & Koch GmbH.