Section 104(5)(iii) in The Central Motor Vehicles Rules, 1989
(iii)two sets of amber coloured side reflex reflectors, one each on left hand and right hand sides of the vehicle, one set as close to the front end and the other set as close to the rear end as possible to the basic machine without attachments and if the distance between the two amber side reflex reflectors is more than 3 metres, additional intermediate amber side reflex reflectors shall be fitted so that the distance between any adjacent amber side reflex reflector is not more than 3 metres :