Using MicroStart technology, Precision TIG Model 275/375 provides arc starting at levels as low as 2 A. Welder''s stable arc easily ramps down and craters out to low amperages for precision work. Suited for specialty alloys and aluminum, Model 275 provides 275 A at 40% duty cycle; Model 375, 375 A. Fan only runs when arc is struck and automatically shuts off.