The Remington ported buckshot choke tube is designed to give you tight patterns downrange with 00 & 000 buckshot. This choke is ported to reduce recoil and muzzle jump that tend to go hand in hand with these large loads. This choke features a constriction designed specifically to optimize patterns with large and small loads alike. This choke will extended about 1" out of the barrel and has a black finish. Machined out of 17-4 heat treated material this choke can be used with Lead, Steel, and Hevi-Shot loads. This choke cannot be used with any Steel Shot larger than BB or with any Steel shot faster than 1550 FPS. Mfg: Carlsons