Weighing in at 1350 grams, our SE4 Youth Polyacrylite Helmet comes with MIPS, incorporating brain rotational protection. This helmet comes with 16 intake ports to channel cool air around and over a rider's head Our new SE4 Polyacrylite Youth Helmet comes with MIPS, incorporating brain rotational protection. This helmet comes with 16 intake ports to channel cool air around and over a rider's head, forcing hot sweaty air out through six rear exhaust ports. This helmet is designed and intended exclusively for off-road dirt bike riding.