Description

Stihl 3639-005-0081 OEM Chainsaw Chain (26RS • 20″)

Genuine Stihl OEM Rapid Super (RS) full‑chisel chain designed for Farm Boss®, Wood Boss®, and professional mid‑range Stihl saws running 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: 3639-005-0081

• Chain Model: 26RS (Rapid Super)

• Bar Length: 20 inch

• Pitch: .325″ (8.25 mm)

• Gauge: .063″ (1.6 mm)

• Drive Links: 81

• Cutter Type: Rapid Super (full chisel)

• Stock Number: 36390050081

• Condition: New OEM

This is the exact OEM chain specified by Stihl for saws equipped with a 20″ .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: 20″

• Pitch: .325″

• Gauge: .063″

• Drive Links: 81

⚠️ 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 a 20″ .325 pitch .063 gauge bar:

• MS 260 Pro

• MS 261

• MS 270

• MS 271 Farm Boss®

• MS 290 Farm Boss®

• MS 291 Farm Boss®

• MS 310

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

Product Specifications

• Brand: Stihl (OEM)

• OEM Part Number: 3639-005-0081

• Chain Model: 26RS Rapid Super

• Pitch: .325″

• Gauge: .063″

• Drive Links: 81

• Bar Length Compatibility: 20″

• 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® and pro 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 Stihl parts specialists

• 🔧 Genuine OEM Stihl products 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 a 20″ .325 pitch .063 gauge bar.

Q: Is this chain OEM Stihl?
A: Yes. This is a genuine Stihl OEM chain, part number 3639-005-0081.

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 3639-005-0081 chain

• Stihl 26RS chain

• Stihl .325 .063 81DL chain

• Stihl MS 261 20 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.