Waiting for a 540 Rescue belay pulley I snagged on eBay for $75.00
Think it functions similar to a belay spool, but not as heavy duty.
"The well-engineered Traverse 540° is a patented, self-locking, easy-to-rig device that meets demanding drop-test criteria: able to hold falling loads quickly while limiting the peak force. The symmetrical design reduces the risk of improper rigging. A built-in release lever discharges the tension on the belay rope, eliminating the need for a release hitch."