5mm Allen Key

A classic tool that remains unbeaten in its versatility

- Simon Richardson

The 5mm Allen key isn’t so much an icon as it is an extension of a cyclist’s right hand.

Any rider worth their salt will have at least half-a-dozen in and around their house at any particular point in time — where they all came from, you’re never quite sure. That you can never find one when you need it is neither here nor there. Many a cyclist’s spouse has had, “Where’s my 5mm Allen key!” shouted angrily at them.