Dimensions and Weight: The Core is 41

Shimano 12-speed

Finish: Black

(can be called BSA or English)

It's to suit posts with a connectamajig (the quick connect bit) at the bottom of the post

PRO 2-10mm Ball End Hex Key Set PLP|Model Year Dimensions and Weight: The CoreThis set of quality chrome plated hex keys from PRO comes in a handy keep holder that is marked with each size so you'll know exactly which size you're grabbing. The hex keys have a ball head at the long end for low torque duties, as well as the standard head at the short end to use when any kind of force is required. The set includes all the sizes you're likely to encounter on a bike. Sizes Included: 2, 2. 5, 3, 4, 5, 6, 8, 10mm