FREINO Z is an automatic locking carabiner with friction spur, designed for STOP (D009AA00) and SIMPLE (D004AA00) caving descenders. It allows the user to increase or adjust the braking action during descent. It facilitates the creation of a tie-off. FREINO Z can be rotated in order to limit the risk of dropping the descender when transferred from gear loop to semi-circular carabiner.