I wrote a post specifically about this bit of engineering perfection, but it got no responses. This Allen tri-wrench, aluminum block at the center with plastic coated arms, was our best friend in the bike shop, a tool we used probably more than any other. If I wasn’t using it, it was in the pocket of my shop apron. It rarely was returned to the workbench. The steel 8,9,10 mm socket version wasn’t far behind. I still have one like shown above, with all three arms still in their original plastic coating.

The current Park version, along with its Torx cousin, pale in quality comparison.