Falltech 8447 carabiner large twist lock, 2-1/4 gate opening features: large twist lock 2-1/4 gate opening 3,600 lbs gate with captive pin option rugged forged alloy steel construction user installed steel captive pin helps to guard against misplacement or loss of carabiner when not in use rated at over 8,000 lbs meets the requirements of osha 1926.502 and ansi z359.1-2007/z359.12-2009