Professional Auto-Darkening Welding Helmet is designed to meet the needs of the professional user. The helmet offers the latest safety features while providing maximum performance and comfort. Lightweight & adjustable for complete comfort Ratcheting headgear with sweatband Automatically turns from light to dark and dark to light Responsive lens switching speed up to 0.3ms Welding & grinding mode adjustment conveniently located on outside of helmet Sensitivity and time delay adjustments (4) ARC sensors for high response Includes (2) solar cell 3V lithium batteries Large 3.62" x 1.61" viewing area Meets ANSI Z87.1 and CE EN169/379 standards Product weight: .96 lbs.