... observation, lens size: 7-13# optional China TIG/MIG/ARC/PLASMA welding Safety Welding Helmet ApplicationsWidely used in high-altitude operations ... needs, suitable for Tig welding, Mig welding, Arc welding, and plasma cutting etc.Specifications1). Frame can be flipped for easy observation ... <=0.003%,1300-2000nm<=0.009 China TIG/MIG/ARC/PLASMA welding Safety Welding Helmet