The Figure-8 descender has been use for over 50 years and most hardware manufacturers have made at least one form of this device Belay Device With Ears 40kN Fall Rescue Big 8 Aluminum Descender With Bent-Ears Rappelling Gear Belay Device (Orange Figure 8 Descender Rigging plate for smooth and superb rope control while descending or belaying with easy lock-off, adjustable descent rate, and large main slot Product material: the product is made of aluminum magnesium alloy by hot forging; It has the advantages of high strength, light weight and easy to carry Mabozis 50KN Rescue Figure 8 Climbing Descender Gear It Applies To: Suitable for Mountain Climbing, Rock Climbing, Ice Climbing, Rescue, Working-At-Height, Technical Rope Rescue, Climbers, Cavers and Sport Rappelers