TheseDRS skate/BMX helmets look awesome. The new standard in protective gear. Features Heaps of great colour choices New shape for better fit and styling 14 vents so cool heads always prevail 2 sets of sizing pads DRShelmets meet Australian standards for bicycle helmets. To measure, grab a tape measure and measure the circumference of your head or your child's head just above the eyebrows, this is the best place to measure, match the cm measurement to the measurements below to know what size you are.