Specifications include, but are not limited to: Twenty-nine (29) Ballistic helmets- Rotary Wing Aircrew Ballistic Helmet (ABH) system Reference: Gentex HGU-56/P Aircrew Ballistic Helmet (ABH) Systems (Or Department approved equal). Ballistic Protection: Must meet F1 fragmentation resistance level specified based on US MIL-STD-662E. V50 of 430 m/s using a standard 17 grain bullet fragment. Provide previous helmet Lot Acceptance Test (LAT) results with bid. Impact Protection: Crown area peak deceleration < 150G at 4.88 m/sec impact velocity, headband area peak deceleration < 175G at 6.0 m/sec impact velocity, ear dome area peak deceleration <150G at 6.0 m/sec impact velocity. Shell Penetration Resistance: Shell tear length must not exceed 5 cm after a vertical 5 kg impact from a distance of 1.5 m. Helmet Restoration (pull-test): Helmet chin strap must withstand a 1950 N tension load for two minutes and must not elongate more than 3.8 cm from a 110 N preload. Weight: Must weigh less than 1.5 kg.