Lock Nut Dimensional Standards MIL-S-8879 NASM25027 USAS B46.1 Finish Black Oxide Hex Height 5/64 in Hex Type Thin Light Hex Hex Width 7/16 in Lock Type Flexible Top Material Steel Material Grade/Class Grade 2 Maximum Temperature 1 200 Degrees F Minimum Temperature -70 Degrees F Pack Size Small Pack Removable Yes Resistance Properties Impact Resistant Shock and Vibration Resistant System of Measurement Inch Thread Direction Right Hand Thread Fit 2B Thread Size 1/4 In.-20