Since auto-locking carabiners (also known as twist lock carabiners) are designed to lock themselves shut after being opened, they are a safe and recommended option for many climbing needs. Auto-locking carabiners differ from screw-lock carabiners, which require the climber to manually screw the sleeve onto the gate for a secure lock. Both are excellent options in terms of safety, and the right one for you comes down to preference.