Comfort Innovative design provides operator with 4 axis push button adjustments for maximum comfort . Multiple connection points evenly distribute weight for comfort in all welding positions . Durability Premium industrial grade plastic built to withstand long term use. Simplicity Easy to assemble, adjust and disassemble. Compatible with most non-slotted & slotted hard hat models. *Only for use with Viking® 3250D FGS™ Welding Helmet