Our take: This M135 Element Airsoft upgrade spring is made for most-all airsoft metal gearbox AEGs. Constructed of oil-temper wire with an irregular pitch, it is one of the simplest power upgrades you can do for your metal gearbox AEG. High quality, low price tag. Get more power out of your AEG today! FPS rating: 410 - 450 FPS
Disclaimer: Any and all airsoft upgrade parts purchased from Airsoft Megastore will be used/installed at owner's discretion. We are not responsible for any damage that may occur. For best results, please do all upgrades at a certified professional airsoft technician/shop.