Above: D03: D03 uses Single Wall (A) Cardboard with a thickness of 5mm, which is one third that of the (AAc) board. The number of ribs in every direction has been increased to 12. The maximum width of the ribs on the top of the helmet is 40mm and that on the base of the helmet is 30mm.
Problems:
• Bulky due to the 40mm thickness, which has to be maintained due to single wall cardboard.
• Flat base plate adds to the bulky nature of the helmet.
