Shell should be dome shaped, no metallic components are to be used. Brim diameter should be 6mm, peak 50mm.Diameter of the hole for ventilation should not exceed 6mm and maintained at a distance not less than 15mm from adjacent hole. Number of holes should be more than 3 but the average area of all holes should not exceed 300mm2.
The headband should be more than 30mm in width. Cradle should be secured at minimum of four anchoring points. Straps should be anti-concussion and width not less than 19 mm.Straps should be fitted such that minimum clearance be at least 30 mm and maximum clearance more than 80 mm.
Chin strap should have minimum width of 19 mm and directly attached to shell. Nape strip should have minimum depth of 115 mm.
The mass of helmet without attachments should be 400 g. If it is to exceed 400 g, with nearing 35 g, it should be labelled.