Pin, Tensile 3/8" Diameter 3-3/4" Locking Space w/ YELLOW 1-7/16" Jumbo Round Knob - Universal Weight Stack SELECTOR KEY - 3/8" Diameter DETENT Hitch Locking - w/ Bronze Insert ** Please make sure you are ordering the correct length pin for your weight stack. When measure, pin should go through stack, selector stem and well into the other half of the plate. The pin should cover up to at least 75% of the stack depth. Magnetic pin lock space measure true to length. The Diameter of the Shaft is 3/8" Pin, Tensile 3/8" Diameter 3-3/4" Locking Space w/ YELLOW 1-7/16" Jumbo Round Knob - Universal Weight Stack SELECTOR KEY - 3/8" Diameter DETENT Hitch Locking - w/ Bronze Insert