direct replacement trigger switch for part# 227 798 for your Miller or M Style style gun, it fits your M10 , M15 , M25 . This trigger design was used on many different Millermatic Mig Welders models. This also fits your Hobart H-10 , H-14 guns found on the Handler 135 /140 / 175 / 180 / 187 / 210 and 210MVP If you have a M-100 or a M-150 your trigger is Blue this trigger will not work,