Ryobi AC04021 OEM 20-Inch Bagging Blade for 40-Volt Cordless Brushless Lawnmower

What It Is

This is a genuine OEM replacement blade designed for Ryobi 40-Volt cordless brushless mowers with a 20-inch deck. It’s a bagging blade—its lifted wing profile creates stronger airflow to pull clippings into the bagger, rather than mulching or side-discharging.

Fitment & Compatibility

• Deck size: Must be exactly 20 inches. Measure your current blade tip-to-tip—this won’t fit 21-inch or 19-inch decks.
• Model check: Works with most Ryobi 40V 20-inch brushless mowers (e.g., RY40180, RY40180US, RY40180BTL, RY40190, RY40190US). Check your owner’s manual or existing blade part number.
• OEM vs aftermarket: This is Ryobi OEM, so fit, balance, and hole pattern are guaranteed. Aftermarket blades may cost less but often need filing to center properly.
• Measurements: 20-inch length, 0.125-inch thickness, 1-inch center hole, 5-point star drive pattern. Verify your blade’s center hole shape before ordering—some Ryobi models use a different keyed slot.

Key Things to Know

• Installation difficulty: Easy (one bolt, star lock washer). Use a torque wrench to 30–35 ft-lbs—overtightening strips the aluminum adapter.
• Sharpness out of box: Comes sharp but not razor-edged. It’s designed for lift, not slicing. Dull faster in sandy soil.
• Common gotcha: The star drive pattern is specific to Ryobi 40V mowers. If you have an older Ryobi 20V or gas model, this blade won’t fit.
• Balance: OEM blades are balanced from factory. If you sharpen it, re-balance on a blade balancer to avoid vibration.

Should You Buy It

Buy this if you have a Ryobi 40V 20-inch brushless mower and want reliable bagging performance with no fitment guesswork. Skip it if you mulch or side-discharge—this blade’s lift design hurts mulching quality. At $40, it’s a fair price for OEM reliability, but check your center hole pattern first to avoid returns.