-Our Nic-O-Loy Keyhole 4-Loop Retraction Arch is a Nickel Cobalt wire similar to Rocky Mountain's Blue Elgiloy. -Nic-O-Loy allows severe bending without risk of fracture and may be heat treated to increase tensile strength and resiliency dramatically. -50 wires (5 each size) in Looped Archwire Rack. **For further product information, please contact Chat Support**