The Air Traffic Controller (or ATC) has a cone shape that encourages non-jamming rope feeding. Particular attention has been paid to the slots, which are designed with an elliptical shape similar to a bight of rope. The dynamic braking quality, which allows rope to slip through the device, is important in limiting forces on the belay chain. The walls are somewhat less thick on the ATC and, as with other devices, will wear thinner over time.

• For twin, half, or single rope belay and rappel.
• Integral rigid keeper wire won’t get sucked into slots.
• Unique, sooth-handling geometry
• Material: Aluminum alloy
• Handles ropes from 7.7 to 11 mm
• Type:  Tubular 
• Weight :  55g
• Made in: Taiwan