Master Lock - 5 Trailer Locks Keyed Alike 5KA-37940 Total trailer security Keyed Alike - One key opens all five (5) locks. Multiple 5KA trailer lock packages CAN be keyed alike. If you ordered a quanity of 2, 3 etc we would automatically key them all the same. Round padlocks 2-3/4" (70mm) wide laminated stainless steel body resists corrosion. Each lock comes with two keys, for a total of ten keys. Coupler lock fits 1-7/8", 2" & 2-5/16" couplers.