I've usually used SRAM or a Sunrace on a Shimano chain. Both for my 11spd and 10spd bikes. Obviously buying the right part for each.

I went with a KMC this time for my 10spd, totally didn't work. Super super super loose. Loose to point it doesn't connect at all if you assemble it by hand on the chain, or off of the chain.

Took them to the LBS. They tried them on their chains of all types, same loose issue. They were concerned. They took out their own KMC missing link supply, same issue.

I got mine from Amazon. They didn't recall the supplier they used that time.

I've emailed KMC the info and offered to ship them what I have.

Anyone else having issues? LBS and myself both got counterfeit product by chance?