Durable heavyweight construction specifically designed for rigging and rescue applications. These are no lightweight rock climbing ascenders! Easy to operate with a gloved hand, these ascenders come with large thumb release on cam, large molded handgrip, and double clip-in points. Unique cam design allows for increased strength. Will accommodate 9 to 13 mm ropes. Strength (frame) 6000 lbf. They are sold as a pair.