Giro Atmos Cycling Helmet One helmet Separate tensioning and position adjustments plus a soft rubber over-molded fit belt that hugs your head in luxury In-mold technology fuses the shell with the liner resulting in light, cool, and tough helmets weighing 9.5 oz./ 275g Wind tunnel ventilation is Giro's proprietary system of internal channels and active vents that force cool, fresh air 1 year warranty