Wipperman Connex connector. Sram is advertised as 'one use'..as in install but not disconnect and reuse. In their video that state it's 'not resueable'. Interesting they also say they have the only 10s chain that connects with a 'masterlink. 'Only 5.9 chain with a toolless attach device that you will find in cycling today'..kinda like the 'first' sub 2000 gram group..Record, Wipperman, shimano 7900.