Skull Style Gas Mask for Outdoor War Games - Black This product is not for the appearance of anti-virus protection products. It's used for outdoor survival game, shooting training and acting. Free Size Length 19cm Width 17cm Full Face Goggle Mask with Fan Ventilation System Large space inside goggle, able to wear most glasses inside the mask Fan with 2 speed levels, can operate ~150mins for normal mode & 50mins for high speed mode