This multi-purpose belay/rappel device is lightweight and easy to use. The asymmetrical V-shaped grooved friction channels adapt the friction on the rope according to its diameter and condition (ARC -Adaptive Rope Control- technology) Ultra-light design: - minimalist construction - hot-forged aluminum - weight: 77 g A single device for all rope types: - effective braking on half and twin ropes ¡Ý 7.5 mm - effective braking on single ropes ¡Ý 8.9 mm - can belay the leader, one or two seconding climbers and can be used for rappelling - independent and simultaneous belaying of one or two seconding climbers in Reverso mode - quick changeovers from Reverso mode to belaying the leader when climbing multi-pitch routes V-shaped friction channels: - increased friction on thin ropes - friction is adapted for larger diameter ropes - increases the locking pressure on the ropes in Reverso Mode Asymmetrically grooved sidewalls: - increased braking power during a leader or top rope fall or while rappelling - rope smoothly slides through device when taking up slack Carabiner hole to release device when loaded  in Reverso mode: allows the loaded device in Reverso mode to be easily and gradually released with only a carabiner Rope friendly, facilitates belay and rope handling: - will not kink the ropes regardless of the mode used - separates the two strands of rope when belaying and rappelling Intuitive use: - Reverso mode attachment point is easy to identify - keeper cable keeps the device from moving up the rope when belaying and reduces chances of losing the device - usage diagrams (standard belay and Reverso modes) engraved on device Use with symmetrical shaped locking carabiners (Am'D or OK) to maximize efficiency no matter which end is closest to the device. Specifications Weight: 77 g Material: Hot forged aluminum body (6082 ALU) Available in three colors: - green (D17 G) - blue (D17 B) - titanium (D17 T) For use on: - single ropes ¡Ý 8.9 mm - half ropes ¡Ý 8 mm - twin ropes ¡Ý 7.5 mm 3 year guarantee