Stihl 3639-005-0074 OEM Chainsaw Chain (26RS • 18")

Genuine Stihl OEM Rapid Super (RS) full-chisel chain designed for Farm Boss® and legacy mid-range Stihl saws using a .325 pitch, .063 gauge setup. This is the factory-correct 26RS chain loop — not aftermarket — sold by P&P Small Engines.

Product Overview

• Brand: Stihl (OEM)

• Stihl Part Number: 3639-005-0074

• Chain Model: 26RS (Rapid Super)

• Bar Length: 18 inch

• Pitch: .325" (8.35 mm)

• Gauge: .063" (1.6 mm)

• Drive Links: 74

• Cutter Type: Rapid Super (full chisel)

• Stock Number: 36390050074

• Condition: New OEM

This is the exact OEM chain specified by Stihl for saws equipped with an 18" .325 pitch .063 gauge guide bar.

Verify Fitment in 30 Seconds

Before ordering, confirm the following on your guide bar or current chain:

• Bar Length: 18"

• Pitch: .325"

• Gauge: .063"

• Drive Links: 74

⚠️ Full-chisel RS chains are intended for experienced users and perform best in clean cutting conditions.

If you’re unsure about fitment, contact P&P Small Engines and we’ll help verify compatibility before you order.

Compatible Stihl Models

This OEM Stihl chain fits the following models when equipped with an 18" .325 pitch .063 gauge bar:

• MS 270

• MS 271 Farm Boss®

• MS 290 Farm Boss®

• MS 291 Farm Boss®

• 027

• 029

⚠️ Model alone does not guarantee fitment — bar specifications must match.

Product Specifications

• Brand: Stihl (OEM)

• OEM Part Number: 3639-005-0074

• Chain Model: 26RS Rapid Super

• Pitch: .325"

• Gauge: .063"

• Drive Links: 74

• Bar Length Compatibility: 18"

• Use Type: Firewood cutting, landowner use, professional cutting

Why Choose an OEM Stihl Rapid Super Chain?

• ✅ Full-chisel cutters for fast, aggressive cutting

• ✅ Designed for higher-torque Farm Boss® saws

• ✅ Excellent performance in clean wood

• ✅ Manufactured to exact Stihl OEM specifications

• ✅ Avoids fitment and safety issues common with aftermarket chains

OEM Stihl RS chains deliver maximum cutting speed and reliability.

Why Buy From P&P Small Engines?

• 🔧 Knowledgeable small-engine specialists

• 🔧 Genuine OEM Stihl parts only

• 🔧 Fitment support before purchase

• 🔧 Fast, careful shipping

We help you get the right chain the first time.

Frequently Asked Questions

Q: Will this chain fit my MS 271 Farm Boss?
A: Yes, if your MS 271 is equipped with an 18" .325 pitch .063 gauge bar.

Q: Is this chain OEM Stihl?
A: Yes. This is a genuine Stihl OEM chain, part number 3639-005-0074.

Q: What does Rapid Super mean?
A: Rapid Super is Stihl’s full-chisel cutter design, built for fast cutting in clean wood.

Common Search Terms

• Stihl 3639-005-0074 chain

• Stihl 26RS chain

• Stihl .325 .063 74DL chain

• Stihl MS 271 Farm Boss 18 inch chain OEM

• Stihl Rapid Super chain

Questions?

If you need help confirming bar compatibility or selecting the correct chain, contact P&P Small Engines — we’re happy to help.