The TempaComp is a compass and thermometer wrangled into a carabiner form factor. It's obviously not meant to bear loads, but borrows the form for the sake of convenient attachment. It's also got a brass split-ring up top.
There are actually two compasses. The one oriented around the side of the bubble shows the direction of travel.
Made by outdoor gear brand Sun Company, It weighs just 1.12 oz., and runs $13.
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