Stihl 029, 039, Ms290, Ms310 And Ms390 High Speed Grooved Ball Bearings For Both Sides Of The Crankshaft, Replaces Stihl Parts # 9503-003-0440. These Are High Performance Bearings For High Speed And Load Of The Chain Saw. Crankshaft Seals For Both Sides Of The Crankshaft Replaces Part # 9639-003-1743. You Will Get 2 Bearings And Two Crankshaft Seals
- Noise tested before and after lubrication
- Passes V2 noise vibration standards for smaller bearings and V3 standards for larger bore
- Matched ABMA grade 10 precision balls for roundness
- Finely honed superfinished raceways for long life and low noise
- Meet or exceed ABEC 3 tolerances for high quality level