Yeah, based on what we found, the 8TEN LawnRAZOR Mower Blade should fit Troy-Bilt 21' mowers. While it was highlighted for the Cub Cadet CC999ES, both the manufacturer's description and some feedback indicate it works with various brands, including Troy-Bilt.
The blade itself is 20 3/4 inches long, 2 1/4 inches wide, and has a center hole diameter of 11/16 inches.
I'd suggest you compare these details with your current mower blade just to make sure everything checks out with your specific Troy-Bilt model. It's always smart to double-check since there can be slight differences in models.
As for how it performs, folks generally like the 8TEN LawnRAZOR for its mulching and cutting prowess. It's seen as pretty efficient and reliable for keeping your lawn nice.
Just a heads up, though—some noticed it wasn't super sharp out of the box. This might be because of a powder coating applied to protect it during shipping.
If it seems a bit dull at first, a quick manual sharpening should get it to peak performance faster. Once sharpened, it seems to make clean cuts and leaves the lawn looking great.
All in all, for a Troy-Bilt 21' mower, this blade should work, provided the model is listed as compatible. A bit of manual sharpening might be needed for it to work at its best, so you should keep that in mind.
Otherwise, it seems like a solid choice for your mower.
