I use a Trimax 100. I bought receiver locks for all vehicles, several pin locks, several spare tire cables with built-in locks, bike cables, and a couple Trimax 100's for several trailers. They are all keyed the same with a barrel style key. Better security, and no hunting for different keys. Better yet, i bought stainless. Theyll outlast me. I bought them all with plenty of spare keys from Heartland Lock.