SRAM continues to innovate the chains that continue to win races around the world. The new PC 1051 10 speed PowerChain featuring the PowerLock connecting link provides smooth, precise shifting and weight savings. Compatibility extends to industry-standard 10 speed systems. PowerLock. SRAM chain engineers developed PowerLock as a tool free, sure and consistent way to connect our 10 speed chains. While PL does not require special tools for install, the especially tight tolerances of 10 Speed drive trains mandated that each PowerLock is good for a one-time application only.