Cup-and-cone hub bearings require a specific kind of wrench — one thin enough to slip onto the cone locknut without interfering with the adjacent locknuts or axle hardware. Standard open-end wrenches are too thick to reach. Park Tool's DCW-2 Double-Ended Cone Wrench solves the clearance problem with a thin-profile steel body that carries 15mm on one end and 16mm on the other, covering the 2 most commonly encountered cone sizes on road and mountain bike hubs.

The double-ended layout means you get 2 wrench sizes in a single tool, which cuts down on what you need to carry in a saddlebag or home toolbox. Hub overhauls typically involve holding one cone with a wrench while turning the locknut with another, so having the right size pairing on one tool streamlines the process. The 15mm and 16mm combination applies to a wide range of Shimano hubs and many other manufacturers' cup-and-cone designs. If you're not sure which sizes your hubs use, measure the cone flats with a caliper before ordering — cone dimensions vary across hub models and brands.

The DCW-2 is nickel plated and heat treated for corrosion resistance and durability at the tool faces. The open-end heads are angled to provide clearance around axle hardware, and the wrench includes a hang hole for pegboard or hook storage. This is a maintenance-weight tool built for the torque levels involved in cone adjustment — it's intentionally thinner than a standard wrench to fit the narrow gap between cone and locknut, so it's not designed for high-torque applications like pedal installation.