DoubleStar Twang-Buster Black. Eliminates annoying twang sound when weapon is fired. Specifications for DoubleStar Twang-Buster: Manufacturer: DoubleStar Color: Black Fabric/Material: Derlin Gun Make: AR Platform Gun Type: Rifle Length: 1 in Weight: 0.3 oz Features of DoubleStar Twang-Buster Snaps on to buffer spring opposite buffer Eliminates twang sound Package Contents: DoubleStar Twang-Buster DoubleStar JT140: Twang-Buster Black