Digital controls features variable shade, sensitivity and delay adjustments. Four independent sensors positioned to reduce possibility of blockage during weld. Replaceable lithium batteries (included) with low battery indicator. Versatile 3-N-1 built-in function: Weld, Torch, Grind. Amber view lens allows for enhanced clarity of weld puddle. Technology allows unit to detect welds less than 5 amps. Built-in mag lens holder.