AISEN (Pack of 3 Primer Bulb for STIHL BR350 BR430 BR500 BR550 BR600 Backpack Blower 4238 350 6201 Compatible with STIHL SR430 SR450 backpack sprayer Fit models: STIHL BR350 BR430 BR500 BR550 BR600 backpack blower Fits for Stihl TS410 TS410Z TS420 TS420Z concrete cut off saw Replaces for 4238 350 6201 Package include: 3pcs primer bulb