Material: high quality spring steel and carbon steel, galvanized surface to prevent rust and corrosion. PACK OF 4 .Material: shaft pin is made of good quality spring steel and carbon steel, zinc plated to resist rust and corrosion Size: 1/ 4 inch diameter pin secures coupler latches, jack legs, pintle hooks and more Shape: square and arch retainer wire clip provides a quick latch and added clearance Usage: the fastener eliminates cotter pin loss and fits most quick release applications Wide application: use coupler pins for farm, lawn and garden, trailer hitch receivers, and other applications to secure attachments and PTO accessories