Covers the mechanical and performance requirements for prevailing torque-type steel metric hex and hex flange nuts: - with hex nut nominal thread diameters M3 thru M36; - with hex flange nut nominal thread diameters M6 thru M20; - with specific strength requirements; - for application within the following temperature ranges: - all-metal, plain - minus 50 C to plus 300 C, - all-metal, plated - minus 50 C to plus 230 C, - non-metallic insert - minus 50 C to plus 120 C.