DMM Ultra O Locksafe Carabiner

The DMM Ultra O Locksafe pairs a roomy oval body with DMM's Locksafe three-stage auto-locking gate. It holds pulleys, rope grabs, and rings centered and resists being opened by accident.

Why climbers pick it

The Ultra O has more room inside than most ovals, so it works well when you need several items in one carabiner, such as a micro pulley and a hitch cord eye, or a ring and a sling. The symmetric shape lets those pieces settle in the middle instead of sliding toward the gate.

Locksafe is DMM's three-stage gate: twist, push up, then open. It takes a moment to learn, but it is very hard for a branch, rope, or bark to open it by accident. That is a sensible trade on a connector that sits in the middle of your climbing system.

Inspection and retirement

Before each climb, open the gate and let it snap shut. It should close fully and lock on its own without sticking. Look for cracks, sharp edges, grooves worn by rope, and deformation at the nose or hinge. Sap and grit are the usual cause of a lazy gate, so rinse and dry the carabiner and keep the gate mechanism clean.

Retire any carabiner that has been dropped from height onto a hard surface, shock loaded, or shows wear you cannot explain. Read the markings on the spine and confirm they meet what your system needs. Life-support gear must meet the applicable standard (ANSI Z133 and the manufacturer's instructions), be inspected before every climb, and be used only by trained climbers. See more auto-locking carabiners.