Ryohin Buhin Mag Main Spring for Tokyo Marui VSR-10 Series, Non-Liner, Variable Pitch, MA120 Spring Rate

Compatible Airsoft Guns: ■Tokyo Marui VSR Series ■Maruzen APS-2 Difficulty of Installation: ★★★★☆ | This is a part for advanced users that requires disassembly of the cylinder area, plus any necessary modifications and adjustments. This is a variable pitch spring made by MAG specifically for the VSR series. Variable pitch springs have a section where the pitch (the distance between windings) narrows midway through, and have the following characteristics: - When the bolt is pulled: The "wider pitch section" compresses first with less resistance, followed by the narrower pitch section, resulting in less resistance. When the trigger is pulled: When the spring is released for firing, the "narrow pitch section" expands first, resulting in a stronger initial push.