Draper Expert Auto-Darkening Multi-Use Welding HelmetThis auto darkening welding helmet instantly switches on when the arc is struck and rapidly changes to the required amount of shade. The shade coverage includes 4, 59 and 913. The sensitivity is adjustable using the control panel and there is also a dark to light delay (stepless) function. The helmet is powered by a solar cell and lithium ion battery (replaceable) for fast switching and low amp sensitivity. The 100 x 67mm viewing area provides decent