Alien Technology allows tool to separate into two pieces for more versatility when making repairs.Chain tool is compatible with single- and multi-speed chains, including 10-speed hollow pin (Not 11-speed compatible)31-Tool system separates with the press of a buttonIncludes a nylon carrying caseMaterial Construction: Engineering grade plastic frame with hardened steel toolsDimensions: 3.4 x 1.7 x 1.6"Weight: 290g