The Christensen Arms 3-Prong Flash Hider features multi-length prongs to effectively reduce muzzle flash and eliminate the resonating ping common with traditional 3-prong designs. This is the same flash hider used on Christensen Arms MSR models and is precision-machined from stainless steel for durability and reliable performance. Product Details Caliber: .223 Weight: 2.9 oz; Threads: 1/2 x 28; Fits .920" bull barrel diameter; Material: Stainless steel Caliber: .30 Weight: 2.2 oz; Threads: 5/8 x 24; Fits .920" bull barrel diameter; Material: Stainless steel Multi-length prong design reduces muzzle flash and eliminates traditional 3-prong "ping" Same model used on Christensen Arms MSR rifles