Building a trailer there are a few laws regarding the size and capacity to be legal to use on Public highways.
Dimensions
Trailers on towing vehicles upto 3500kg
Maximum length :- 7m Excluding drawbar
Maximum Width :- 2.3m
Trailers on towing vehicles over 3500kg
Maximum length :- 12m Excluding drawbar
Maximum Width :- 2.55m
Maximum Overall length :- 18m for trailer + Towing vehicle
Maximum Height
Trailers have no Maximum height But it is not recommended to exceed 1.7 x the track of the trailer.
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