RS values of 49, 59, and 70% v/v composite wires and 14-, 16-, and 18-mil SS wires when opposed by 18- or 22-mil SS brackets. When the NFR = 150 cN, the composite wires with a θ = θc′ are comparable to a 16/18 metallic couple at NFR = 300 cN and θ = θc.3,33 Conditions for the metallic AW systems: AWs = 18 mil SS (Round, Ormco), 16 mil SS (Gold Tone Round, American Orthodontics), and 14 mil SS (Tru-chrome, RMO); BRs = 18 mil SS (Ultra-Minitrim, Dentaurum) and 22 mil SS (Ultra-Minitrim, Dentaurum); state = dry; test temperature = 34°C; NFR = 300 cN; IBD = 16 mm. Conditions for the composite AW system: AWs = 20 mil S2-glass composite (UNC); BRs = 22 mil SS (Uni-Twin, Unitek/3M); state = dry; test temperature = 34°C; NFR = 150 cN; IBD = 16 mm