The HGU-55/E is identical to the standard HGU-55, except that a protective visor assembly replaces the bungee visor.  Its protective visor housing allows easy movement of the impact-resistant polycarbonate lens and locks the lens securely up or down.  A size large HGU-55/E with super comfort liner. Earphones, communications cord, and oxygen mask receivers weigh only 37-ounces (1.084 grams).  Helmets include a leather edge roll, comfortable leather earpads, and leather chin and nape strap pads.

HGU-55/E helmet features
Visor lens	Impact resistant polycarbonate. Protects from harmful UV rays. Single visor helmet: Dark lens. Optional: Clear, Amber, high contrast, and gradient lenses
Shell composite	Available in Fiberglass or Kevlar® shells
Liner system	Pre-formed Thermoplastic Liner (SCL®)
Weight	Large: 37 ounces (1048 grams) Paint and art affect weight.
Chin strap	Adjustable nylon strap with leather chinpad
Nape strap	Adjustable nylon strap with leather napepad
Edgeroll	Custom fit helmets:  Fit to face (ideal for glasses) Standard fit helmets:  Standard fit
Earpads	Standard:  Leather earpads (sound attenuation 20 db at 100Hz, 39 db at 4000 Hz)   Optional:  Leather earpads with hard plastic cup (sound attenuation 26 db at 100Hz, 43 db at 4000 Hz)
Liner system	Gentex® Super Comfort Liner (SCL) - Standard Gentex X-Liner® Percentile leather covered urethane Custom fit leahter covered urethane
Oxygen mask receivers	Optional: White, chrome plated, or painted to match helmet.  Also available in a light receiver.
Caution	HGU-33, HGU-55, HGU-55/E and HGU-68 helmets have been designed for use in fixed-wing aircraft. They offer limited impact protection.  Users with other applications should consider helmets with greater impact protection designed specifically for their application.
Sizing	Size Head Circumference Head Length  Medium Less then 22 1/2"  7 3/4"  Large 22 5/8 - 23 7/8"  8 1/4"   X-Large Over  23 7/8"  8 7/8"