Section 312(2) in The West Bengal Motor Vehicles Rules, 1989
(2)The mark shall be kept clean and unobscured and shall be so fixed to the trailer that -(i)the letter on the mark is vertical and easily distinguishable from the rear of the trailer;(ii)the mark is either on the centre or to the right hand side of the back of the trailer; and(iii)no part thereof is at a height exceeding one hundred and twenty centimetres from the ground.
