Oregon S40 chain: what it fits and what the code means
S40 is a 3/8" LP pitch, .050" gauge chain with 40 drive links. It fits 347 saws listed below.
What S40 is
- Pitch
- 3/8" LP
- Gauge
- .050"
- Drive links
- 40
The letter S is the chain type, the number 40 is the drive link count.
Buy this chain
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Check pitch, gauge and drive links on the listing before you order. How this works
Same length, different chain
The number is the length; the letter is the chain. These all have 40 drive links:
| Code | Type | Pitch | Gauge | Family |
|---|---|---|---|---|
| S40 | 91PX | 3/8" LP | .050" | AdvanceCut |
| R40 | 90PX | 3/8" LP | .043" | AdvanceCut |
R40: different pitch or gauge. Not a substitute for S40.
Saws that take S40
Craftsman · 147
Western Auto · 16
Sun Joe · 2
Black+Decker · 1
Corona · 1
Questions people ask
What does S40 mean on an Oregon chain?
S is the chain series (91PX, AdvanceCut: 3/8" LP pitch, .050" gauge). 40 is the number of drive links.
What bar length is S40?
Usually 10". What matters is the drive link count, 40: count the links on your old chain rather than going by the inches.
What file do I need for S40?
A 5/32" round file.

