The NEXUS SF Helmet (Special Forces Helmet) is cut higher around the ears for tactical headsets comms fit. The higher cut helmet offers enhanced peripheral vision, are lower in profile and lighter in weight. The Nexus S.F. Helmet has no lip or ear coverage and is ideal for Special Forces, Snipers and Counter Terrorist Teams. FEATURES High ballistic performance with low weight, using high-tenacity ballistic aramid fibre and bound in a Thermoplastic resin matrix. SUSPENSION SYSTEM 4 point chin strap harness, with an integrated crown mesh with cross straps with plastic chin cup. RAILS SRS (Side Rail System) provides a low profile platform which can accommodate tactical lights, IR Lights, video cameras and goggle straps. Snag free for HALO, HAHO and static line. SIZES The SF helmet has a fully adjustable harness system. Size EURO (circumference) UK (circumference) USA (diameter) Weight Medium 54-59 cm 21-23 inch 6 5/8″ – 7 1/4″ 1.2Kg Large 56-64 cm 22-25 inch 7 1/4″ – 8″ 1.3Kg   BALLISTIC PROTECTION NIJ Level IIIA 9mm – .357 and 44 Magnum. V50 Fragmentation Rating up to 750 m/s; as tested with 1.1g, 22 Caliber, 17 grain Fragment Simulated Projectile, according to STANAG 2920 and US MIL STD 662F. Ballistic (National Institute of Justice)NIJ II 9mm FMJ and 357 Magnum JSP, in accordance with NIJ standard 0106.01. It has a V50 of 550 m/s (1800 ft/s). NIJ IIIA 9mm FMJ and 44 MagnumSJHP, in accordance with NIJ Standard 0101.04. (June 2001). It has a V50 of 610 m/s (2000 ft/s).