42" & 46'' Deck Mulch Tractor Mulch Cover Kit Fits for Cub Cadet RZT-42 Troy-Bilt TB46 Mulch Plug Assembly

What It Is

This is a mulch cover kit (also called a mulch plug assembly) that blocks the discharge chute on 42" and 46" cutting decks, forcing grass clippings to circulate under the deck for finer mulching. It’s designed for Cub Cadet RZT-42 and Troy-Bilt TB46 zero-turn mowers.

Fitment & Compatibility

• Deck size: Only fits 42" and 46" decks. Measure your deck’s cutting width before buying—don’t guess.
• Specific models: Confirmed for Cub Cadet RZT-42 (all series) and Troy-Bilt TB46. Not listed for other Cub Cadet or Troy-Bilt models—check your owner’s manual or measure deck opening.
• OEM vs aftermarket: This is an aftermarket part, not genuine Cub Cadet. Fitment should match OEM part numbers 490-110-0004 (Cub Cadet) or 490-110-0005 (Troy-Bilt). Verify these against your deck.
• Mounting points: Uses existing bolts/holes on the deck’s discharge opening. No drilling required, but ensure your deck has the two mounting holes (usually 2.5" apart).
• Blade check: Works with standard mulching blades. If you use bagging or high-lift blades, you’ll need to swap to mulching blades for proper performance.

Key Things to Know

• Quality: Made of heavy-duty polyethylene plastic—durable but can crack if over-tightened or hit debris. Hand-tighten bolts only.
• Installation: Takes 5-10 minutes. Remove the discharge chute (if present), align the plug over the opening, and secure with the included bolts. No tools beyond a socket wrench.
• Gotcha: The plug must sit flush against the deck. If it gaps, clippings will escape and mulching quality drops. Check for bent deck edges before installing.
• Mulching vs side-discharge: You cannot use this with the side chute attached. Remove the chute first. Switching between modes takes about 2 minutes.

Should You Buy It

Buy if you own a Cub Cadet RZT-42 or Troy-Bilt TB46 and want cleaner mulching without bagging—especially on flat lawns with dry grass. Skip if you have a different deck size, need a genuine OEM part for warranty reasons, or prefer side-discharge for wet/tall grass. At $26.50, it’s a cheap upgrade that works as advertised.