Yard Force 21-Inch 3N1 Lawn Mower Blade Replacement for YF22-3N1SP, YF22-3N1SP-SC & YF22-3N1SPVS-SC | OEM Part 1253556001 | Precision-Cut Steel, Dual-Edge Mulching Blade

What It Is

This is a direct OEM replacement dual-edge mulching blade for Yard Force 21-inch 3-in-1 mowers (bag, side-discharge, mulch). It’s designed to fit specific 21-inch deck models that use the 1253556001 part number.

Fitment & Compatibility

Before buying, confirm three things:

• Deck size: Must be exactly 21 inches. Measure your deck width, not the blade length.
• Model number: Fits Yard Force YF22-3N1SP, YF22-3N1SP-SC, and YF22-3N1SPVS-SC only. Check your mower’s model tag (under the seat or on the deck).
• OEM vs aftermarket: This is genuine Yard Force, so it matches factory specs. Aftermarket blades may vary in thickness, hole size (center hole is 1 inch), or blade offset. Measure your old blade’s length (21 inches), width (about 2.5 inches), and center hole diameter before ordering.

Key Things to Know

• Installation difficulty: Easy—one bolt per blade. Use a socket wrench (usually 5/8 inch or 3/4 inch). Torque to 35-45 ft-lbs. Wear gloves; blades are sharp.
• Dual-edge design: Both sides are cutting edges—rotate the blade when one side dulls to double lifespan before sharpening or replacing.
• Common gotcha: The blade is directional. The “air lift” curve must point upward (toward the deck) when installed. Wrong orientation kills mulching performance and can vibrate.
• Quality: 0.25-inch thick steel, heat-treated. Holds an edge well for a season of normal use, but avoid rocks or thick roots—they’ll chip it.

Should You Buy It

If you own one of the three listed Yard Force models, this is the correct, hassle-free replacement. It’s a solid OEM part with good durability and easy installation. Skip it if you have a different brand or a non-21-inch deck—fitment won’t work.