Presta Valve Core Pack (12 Units) + 12 Anodized Alloy Presta Valve Caps for Tubeless Road & MTB Bikes, Compatible with Stan's, Vittoria, Continental, Kenda & MORE. LeaK-Proof Replacement for Presta and Schrader Valve Cores Review

I use valve caps on the MTB, the valve cores are great, have had to replace them over time as o-rings wear out or stans stick them together and I can't clean 'clean'.

They fit me perfectly. I have these clogs fairly regularly because of the sealing. They lasted as long as everyone else. Metal caps are a nice bonus. I will say like others that the red caps are more pink.

I run tubeless on my mountain bikes with valve stems that use removable valve cores and this set of 12 is perfect for servicing. However, I only gave this 4 stars because the "red" valve caps are not red, they are more of a pink color which doesn't match any red I have on the bike.

These cores work great in stan valve stems in derby rims with HRII/DHRII tires. Added details to give information about the application here. I actually ordered this for aluminum caps as my plastic caps often tear and I am very happy with the caps. My goal is to keep debris out of the valves to reduce sand ingress into the valve core seal. I will buy again.

I fitted these to my mountain bike and the tire went flat within a few hours. I replaced the core with another one from the pack and it held up. The thought was an accident. Well after a few days I installed them on my fatbike - same problem. Basically you have to keep installing them until you find one that will hold air. Doesn't inspire much confidence if you're driving in the woods and don't want to deal with a flat.