ICON Airflite™ Motorcycle Helmet - Jewel - MIPS® - Gold - Large 0101-13885 Monster 821 2017/2021 It has a round shape

It has a round shape with a diameter of 3

ABS plastic

It is constructed with a carbon-fiber muffler outer sleeve and end cap

Racing exhaust Reference: MD

ICON Airflite™ Motorcycle Helmet - Jewel - MIPS® - Gold - Large 0101-13885 Monster 821 2017/2021 It has a round shapeInjection molded polycarbonate shell for strength Multiple oversized intake and exhaust ports Fog Free Dropshield with exterior switch Quick change Fog Free Fliteshield with sideplates Removable molded breath deflector and chin curtain Recessed twin channel supervent cooling system The Dropshield visor must only be used while the main face shield is in the fully closed position Internal speaker pockets work with ICON's R. A. U. Bluetooth device