It fits the flats and tightens traditional fixed cups on cup-and-cone bottom brackets. A $140 shop tool is better, but this affordable hand tool will do the job, too.

Here’s how: First turn the cup counter-clockwise (on most non-Italian frames) until it’s as tight as you can get it without the wrench slipping off.

Then have a friend hold the wrench onto the fixed cup and keep it from sliding off by pushing the heel of a hand on it, against the bottom bracket while the other hand stabilizes the wrench handle.

Then you get the side of a metal hammer and whack the handle of the wrench with the side of a hefty hammer to screw it on there really snugly.
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Intentionally made without plastic or vinyl handles for the environment’s sake. We recommend you wrap them with Newbaum’s Cotton Tape and finish the ends off with twine. The tool factory Rivendell contracted with took about a month to wrap their head around the idea.