USA Mower Blades 2 AYP340BP Mulching Blade Fits AYP Craftsman 127843 134149 138498 138791 138971 139775 24676 Length 21 in. Width 2-1/4 in. Thickness .134 in. Center Hole 5 PT ST 42 in. Deck

What It Is

This is a set of two 21-inch mulching blades designed for 42-inch deck Craftsman and AYP (American Yard Products) lawn tractors. They replace OEM part numbers 127843, 134149, 138498, 138791, 138971, 139775, and 24676, intended for fine grass clipping mulching rather than bagging or side discharge.

Fitment & Compatibility

Before buying, verify the following:

• Deck size: Must be exactly 42 inches (not 38, 46, or 48 inches).
• Blade length: 21 inches from tip to tip. Measure your old blade’s length to confirm.
• Width: 2-1/4 inches wide. Some decks use narrower blades—check clearance under the deck.
• Thickness: .134 inches (standard for most AYP/Craftsman decks).
• Center hole: 5-point star (5 PT ST) pattern. This fits AYP/Craftsman spindles with a star-shaped drive. It will not fit round or oval holes.
• Model compatibility: Fits Craftsman models using the OEM numbers listed above. Also fits many AYP, Husqvarna, Poulan, and Sears tractors with 42-inch decks and star-shaped spindles. Search your mower’s model number (not engine model) to confirm.

Key Things to Know

• Mulching vs. standard: These are mulching blades with a curved, serrated design. They do not have a high lift for bagging—expect clippings to stay under the deck.
• Installation difficulty: Easy—remove the center bolt (usually 5/8 or 3/4 inch), replace blade, torque to 70-90 ft-lbs. Use a blade stop or block of wood to keep the blade from spinning.
• Common gotcha: The “2 AYP340BP” in the title means a set of two blades. Some sellers list singles—verify you’re getting two if your deck uses two blades (most 42-inch AYP decks use two).
• Quality: Aftermarket, but made from hardened steel. Reviews note good balance and durability for the price. Check for sharp edges—some users deburr before installation.

Should You Buy It

If you have a 42-inch AYP or Craftsman tractor with a star-shaped spindle and need mulching blades, this is a solid, budget-friendly choice. It’s not for bagging or side discharge, but for mulching grass clippings into fine particles, it works well and fits common OEM part numbers. Avoid it if your deck uses a different blade center hole or if you need a high-lift design.