JSP's EVO®5 DualSwitch™ is fully certified to both EN397 and EN12492, with the ability to change between the two standards easily at the flick of a switch. Working on the ground - Switch up, The chinstrap release force of EN397 is between 15-25kg (approximately). This limits the risk of choking, the chinstrap has been designed to release if snagged. Working at height - Switch down, The chinstrap release force of EN12492 is greater than 50kg, (approximately). This limits the risk of losing the helmet during a fall. Featuring a fully adjustable 4-point chinstrap, an easy to use Revolution® wheel ratchet and a 3D adjustment harness, which offers 1-2-3 point depth settings for a perfect fit.