Review on Topeak Presta Valve Extender by Jeffrey Sanders

Will not fit Reynolds Assault holes (fairly typical valve hole size). Also, the brass valve tip should make contact with the end of the valve core that you left in the original valve. It doesn't snap easily, making it difficult to easily open and close the valve. I suppose if you insist on using tubes with non-removable cores this is a good design, but if you just go for tubes with removable cores you can get an extension that works much better and easier. Also, one of them broke with the force required to screw my 42mm Contitube stem onto the valve stem. I do not recommend. If you're spending money on high profile rims, you should probably look for better extensions than this one.