Qauick Carburetor Carb Fits Stihl Backpack Blowers Sr320 Sr340 Sr380 Sr400 Sr420 Br320 Br340 Br380 Br400 Br420, 4203 120 0601, 4203 120 0603, 4203 120 0605, 4203 120 0607 & Walbro Hd-4a Hd-4b Hd-13b