MTEK FLUX Helmet Cover-Gen4Details Sizing Specs Returns The Gen4 MTEK Version is a next generation helmet cover that fits the MTEK FLUX helmet like a glove and gives it new, cutting edge functionality and universal accessory management. It employs a new versatile rear flex cell that fits all common NVG battery packs, counterweights and has strategically placed exit holes for all cables. The semi rigid cell exterior gives rear accessories extra impact protection and has a