Will the Kmc missing link 6-8 speed work on any 6-8 speed chain?

KMC has introduced Series II Missing Links which are a different width than the first Series of Missing Links. To determine whether you need an Original Missing Link, or s Series II Missing Link, you need to measure the width of the chain the Link will be used on.

The difference between Original and Series II Missing Links is .2mm.

Which is very small an amount but everything if you fall on the tight side of the fence. Andy.

This was discussed in another thread recently. It's making me wonder what type I have. I had issues with the SRAM ones being too tight on Shimano chains and bought a bag of the KMC links. They seem to work well and fit just right on Shimano.

The problem I see is that KMC is not marking the packaging that their chains come in with which Missing Link is the correct one for the chain contained. Maybe they don;t think it's important since a Missing Link is included in the box, but how do they expect customers to buy the correct replacements?

It's only an issue for the original 6/7/8 speed connectors. They expect you/someone else to measure the length of the pin in your chain. You would then buy the appropriate link. As Andy said, that little bit matters...especially when attempting to use a Missinglink with another brand chain, since pin length on the chain doesn't necessarily mean that the quick link will fit. You can also note the model number pressed into the quick link you have, and buy the appropriate replacement.

A somewhat different way to look at it is: if you're replacing the quick link for wear reasons, it's probably a good idea to consider replacing the chain, too.