Klein Tools Hard Hats were designed and engineered for optimal safety, comfort and fit. Unique features allow the user to comfortably work in a wide variety of applications and demanding environments. Patent-pending accessory mounts on front and back ensure optional Klein Headlamps attach securely -- no straps needed! Klein Tools Hard Hats were designed and engineered for optimal safety, comfort and fit. Unique features allow the user to comfortably work in a wide variety of applications and demanding environments. Patented accessory mounts on front and back ensure optional Klein Headlamps attach securely — no straps needed Easy, one-handed adjustment with large knob ratchet mechanism even with gloves on, and soft neck pad pivots to clear bandana knots and pony tails This Class E, Type 1 hard hat is tested up to 20kV and meets ANSI Z89.1-2014 (HT and LT), CSA Z94.1-15 EN397:2012+A1:2012-5.2.4 (Lateral Deformation-LD)