SBD's Pop Pins for Exercise Machines. 3/8" x 3" Long Shank POP PINS - Spring Loaded (T or Ball Handle) | Weld-ON

Pull Pin - Round Handle - 3/8" Dia Plunger -3" Length x 1" Diameter

WELDON Steel Barrel -Spring Loaded Plunger -Universal Fitness

Equipment Adjustment Knob.

SB-KP P183E PP 3/8-3 L RH 

• Pop Pins for Exercise Machines. 3/8" x 3" Long Shank POP PINS - Spring LOADED (T or BALL Handle) | WELD-ON Pins/Plungers.
• Spring-loaded pull pin for locating, fastening, and quick change operations. This spring loaded pull pin allows you to retract and engage the plunger for locating, fastening and quick change operations. It consists of a housing (barrel) and a plunger assembly. The plunger assembly screws into the housing. The housing is designed to be welded into place for strength. Pulling on the handle retracts the plunger fully into the pin housing. Releasing the handle allows the plunger to extend.
• Heavy duty spring action pins , used for height and length adjustments on racking systems, fitness and rehabilitation equipment and many other uses.
• Pop Pins, also known as clamp pins, weld-on pins, and spring-loaded plungers.