AC04020 Lawn Mower Blade Compatible with Ryobi RY40180 RY40108 RY40190 RY40109 RY401110 RY401011 RY401120 RY401012 20 Inch 40V Brushless Mowers 2 Packs

What It Is

The AC04020 is an aftermarket 20-inch lawn mower blade set (2-pack) designed specifically for Ryobi’s 40V brushless mowers. It replaces dull or damaged blades to restore cutting performance on residential lawns.

Fitment & Compatibility

• Deck size: Only fits 20-inch mower decks. Measure your blade length before buying—if your deck is 21 or 22 inches, this won’t work.
• Model check: Confirmed compatible with Ryobi RY40180, RY40108, RY40190, RY40109, RY401110, RY401011, RY401120, RY401012. Verify your model number on the mower’s data plate (under the battery or on the frame).
• OEM vs aftermarket: This is a third-party replacement, not OEM Ryobi. It’s a direct-fit design but may differ slightly in steel thickness or balance.
• Measurements: Blade length 20 inches, center hole diameter typically 7/8 inch (common for Ryobi 40V). Check your existing blade’s center hole and offset (if any) to avoid mounting issues.

Key Things to Know

• Quality: 3.9 stars from 22 reviews—mixed feedback. Some users report good sharpness and durability; others note balance issues or faster dulling than OEM blades.
• Installation: Easy—remove the old blade (disconnect battery first!), clean the spindle, and bolt on the new one. Use a torque wrench to 30-40 ft-lbs. No special tools beyond a socket and wrench.
• Gotcha: Aftermarket blades may not be as precisely balanced. If you feel vibration after install, try balancing on a blade balancer or magnetic tool. Unbalanced blades can damage the spindle or cause poor cut quality.
• Pack size: Two blades per pack—enough for one mower (most use one blade). Keep the spare for quick swaps.

Should You Buy It

Buy it if you need a cheap, fast replacement for a Ryobi 40V 20-inch mower and don’t mind occasionally checking balance. Skip it if you prefer OEM reliability (Ryobi genuine blades cost more but are guaranteed to fit and last) or if your mower has a different deck size.