This coupling is identical to its 6 tonne brother, the only difference being the size of the shank on the towpin. The 4.5 runs a 7/8" shank size where as the 6 tonne runs a shank size of 1 & 1/4".
These couplings are ideal for the huge off road caravans that are fully loaded and running big water tanks etc. for when a 3.5 tonne just might not be adequate.
