1500KG - 45mm Round Axle. Suits caravans, campers and tandem trailers.
Suit SL or PARALLEL bearings.
Common problem: Too much weight on this axle will cause bowing in the middle of the axle. Big problem.
Weight your rig at a weight station. Disconnect your caravan from your vehicle and weight that too. Call me when you have done that. I can then help you find a solution.