DMM Ultra O Locksafe Carabiner with Captive Bar

The DMM Ultra O Locksafe carabiner with captive bar is a large aluminum oval with DMM's auto-locking Locksafe gate. The captive bar holds a pulley, device or sling in position so it cannot rotate or slide into a poor loading position.

What the captive bar does

A captive bar closes off part of the carabiner so whatever is clipped there stays put. With a pulley or a friction device, that means the item cannot roll around to the gate side or cross-load when you shift your weight, a common problem on hitch systems with lots of movement.

The Ultra O's oval shape keeps a pulley centered, and the Locksafe gate locks itself when it closes. Many climbers build a dedicated hitch system around a captive-bar oval so the setup stays the same climb after climb.

DMM ovals are a common choice for climbers building their first hitch system because the shape works with almost any micro pulley. Keep the gate clean and lightly lubricated per DMM's guidance so it closes firmly every time, and retire the carabiner if it is dropped onto a hard surface from height or shows grooves at the rope-bearing surfaces.

Use and inspection

Check that the device or pulley fits the captive section correctly and that nothing loads the bar or gate. Read the strength markings and DMM's instructions for the captive-bar version.

Carabiners in a climbing system are life-support gear. Use only connectors rated for the purpose, follow ANSI Z133 and the maker's instructions, load them along the major axis, and inspect the gate, spring and body before each use. Browse our auto-locking carabiners for more.