Lawn Mower Blade for Greenworks 21 inch Mower C3208101 MO40L4413, MO40L03, MO48L4422

What It Is

This is a replacement 21-inch mulching blade designed for Greenworks corded and cordless electric mowers that use the OEM part numbers C3208101, MO40L4413, MO40L03, or MO48L4422. It’s intended for standard residential lawn cutting and mulching on small to medium yards.

Fitment & Compatibility

• Deck size: Only fits mowers with a 21-inch cutting deck. Measure your deck width (not the blade itself) to confirm.
• Model numbers: Works with Greenworks models that list C3208101, MO40L4413, MO40L03, or MO48L4422 as the OEM blade. Check your mower’s manual or the existing blade for these numbers.
• OEM vs aftermarket: This is an OEM Greenworks blade, not a generic aftermarket. It will match the original blade’s hole pattern, center hole diameter (typically 1 inch or 25.4 mm), and overall shape exactly.
• Measure before buying: Compare the length (21 inches), center hole size, and the number/position of mounting holes against your old blade. A mismatch can cause vibration or poor cutting.

Key Things to Know

• Quality: Made from stamped steel with a durable coating to resist rust. Expect good balance and sharpness out of the box, but it will dull faster than premium heat-treated blades.
• Installation difficulty: Easy for DIYers. You need a socket wrench (typically 15/16 inch or 24 mm) and a blade removal tool or block of wood to lock the blade. Torque the bolt to 35–45 ft-lbs.
• Common gotchas: The blade is directional—the curved edge must face upward toward the deck. Installing it upside down will cause poor cutting and vibration. Also, always replace the blade bolt if it’s worn or stripped.
• Mulching performance: The angled wingtips and sharpened edges provide good mulching for dry grass. Wet or thick grass may require a higher-lift blade for better bagging.

Should You Buy It

If you own a compatible Greenworks 21-inch mower and need a direct OEM replacement that’s easy to install and delivers reliable mulching for routine mowing, this blade is a solid choice. It’s not the toughest for heavy commercial use, but for residential lawns, the price and performance match well.