Mammut equipped the Crag Smart HMS Locking Carabiner with a safety gate to prevent cross-loading while belaying. This safety gate also reinforces the twistlock's closure, making it safer than standard locking carabiners. Mammut designed it to pair with the Smart belay device, but it'll make any belay device easier to handle.
HMS carabiner with safety gate is made for belaying and rappelling, especially with assisted-braking belay devices
Safety Gate prevents closing the gate unless screwlock is locked, and prevents the gate from unscrewing during use
Safety Gate also keeps the carabiner properly oriented on the belay loop on your harness to prevent cross-loading, which greatly reduces the strength of the carabiner
Twist-lock gate can only be operated when the Safety Gate is open, preventing the accidental opening of the carabiner gate
Keylock nose won't snag on pro, ropes or slings, making the carabiner simple to clip
Works well with the Mammut Smart 2.0 assisted braking device for those seeking additional security (sold separately)