Strike Industries AR Pistol Flat Wire Spring 10 in Black One Size Black One Size. The Flat Wire Spring design packs more energy than traditional round wire springs giving it increased bolt power. Known for efficiency since the Flat Wire Spring is able to store a larger amount of energy in a smaller space. Having a larger surface area the Flat Wire Spring distributes impact more evenly and reduces wear and tear outlasting the stock spring. Flat Wire Spring design also has less compressing force which increases reliability in cycling and is more resistant to friction and buckling. Specifications for Strike Industries AR Pistol Flat Wire Spring: Manufacturer: Strike Industries Color: Black Fabric/Material: Steel Gun Make: AR Platform Gun Type: Rifle Length: 10 in Condition: New Features of Strike Industries AR Pistol Flat Wire Spring Cryocycled 177 ph steel for strength reliability and longevity Decreased harmonics lessens system vibrations for faster follow up shots Increased spring lifespan No more AR "TWANG" Package Contents: Strike Industries AR Pistol Flat Wire Spring x1 Pistol Length Flat Wire Spring Strike Industries SI-AR-FWS-P: AR Pistol Flat Wire Spring 10 in Black One Size SI-AR-FWS-P Black One Size