Three Prong Knob Screw Length (In.) 1.00 In. Thread Size (In.) 1/4-20 Dia (In.) 1-1/8 In. Base Dia (In.) 1/2 Knob Type Clamp Knob Style Three Arm Material GP Phenolic Finish High Gloss Standards Steel Zinc Plated Height (In.) 0.75 Length (In.) 1.77 In. Overall Height 0.75 Overall Length 1.77 In. Thread Type Course Width -30 to 400 F