SEADOG galvanized steel coupler locking pin. 5/16" diameter. 2"H X 3"L. Sold each.

Square Coupler Pins add an additional level of security, preventing accidental uncoupling while in transit to better protect your trailer. The snap lock bale is spring tensioned for stronger holding power. Fits most coupler sizes. Constructed of electro-galvanized steel for corrosion resistance.