StemCAPtain is a Boulder, CO USA based bicycle accessory company. Our flagship product is the Original StemCAPtain Stem Cap Bike Clock. The StemCAPtain replaces the stem cap, aka top cap, piece of a threadless 1" or 1 1/8" headset with different functional accessories. In addition to the simple and elegant analog clock, we offer a thermometer, bottle opener, picture framecompass, GPS mount, and USB charger, and are always up for suggestions on what to make next. Please take a few minutes to check out our website, and if you see some things you like, we would be happy to take your order online, or just ask for us at your local bike store. StemCAPtains are very easy to install and can be up and running on your bike in just a few ticks.



Replace your bike's stem cap with a brilliantly anodized, CNC machined quartz clock.

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Blazing heat or freezing cold, the thermometer provides a cool look and function.

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Keep on track with one of our compasses. Easily mounts in place of your normal stem cap.

Browse Compasses ›