The GRIGRI's self-braking function helps the belayer catch and hold a climber. Works well for lead climbing and top roping. Its Ergonomic design makes for smooth and very controllable lowers of climbers. Also great for rappelling on single ropes. 

•  Designed For use with single ropes between 10 and 11 mm in diameter
• Its internal cam locks when it receives a sharp pull
• Great for cleaning routes