664P05321A 21" Grassbag Black Std Mesh Compatible with MTD Craftsman M110 M210 M205 M220 M105 M100 Replaces 664P05321 664-05321A 664-05321, (Only The Bag, Frame not Included)

What It Is

This is a replacement grass catcher bag for 21-inch walk-behind mowers, specifically designed for MTD and Craftsman models. It collects clippings during standard mowing, but note it’s only the bag—the metal frame and mounting hardware are sold separately.

Fitment & Compatibility

Before buying, confirm your mower’s deck size is exactly 21 inches (measure if unsure). This bag fits many Craftsman M-series models: M110, M210, M205, M220, M105, M100, plus compatible MTD units with the same bag attachment system. It replaces OEM part numbers 664P05321, 664-05321A, and 664-05321. Critical: Your mower must already have the original frame—this bag slides onto that frame. If your frame is missing or damaged, you’ll need to buy a new frame assembly separately. Measure the bag’s opening width (roughly 21 inches) to match your mower’s discharge chute.

Key Things to Know

• Quality: Standard mesh construction—adequate for dry grass, but fine clippings may blow through. Not heavy-duty; expect moderate durability.
• Installation: Tool-free—just slide bag onto existing frame and hook onto mower. Takes 1–2 minutes.
• Gotchas: The bag alone is useless if your frame is bent, rusted, or missing. Check frame condition first. Also, the bag’s zipper (if present) can jam with wet grass—empty frequently.
• Fitment nuance: Some users report tight fit on older Craftsman models; you may need to adjust the frame’s bag hooks slightly.

Should You Buy It

If you have a compatible 21-inch Craftsman or MTD mower with a functional frame and need a budget replacement for a worn-out bag, this is a solid choice at $33. But if your frame is missing or damaged, factor in the extra cost and effort of sourcing a frame—you might be better off buying a complete bag-and-frame kit.