If you're maintaining a Yamaha Grizzly 450 YFM450FG 4WD from 2007 to 2014, this Caltric bearing kit is what you need.

You get two bearings—silver, chrome-plated metal, each about 55mm long, 13.1mm wide, and 32.5mm thick.
They weigh 9.7 oz total, and they're brand new in packaging.
OE numbers are 93305-00601-00 and 93305-00602-00, and the Caltric part number is BR123AA1055.
Made in China, with a 90-day warranty.

California folks—Prop 65 warning applies, so keep that in mind.

These fit the front and rear, but specifically for this Grizzly model.
If your bearings are noisy or loose, swap 'em out with these and get back on the trail.

Universal?
No, they're made for this ATV, so you know they'll fit right.

Solid metal build, easy install if you've got the tools.