Timken bearings. Quality device at a great price. Always clean the area around the bearing of dirt and debris with a small wire brush before installing a new bearing. Bearing preload is critical, so make sure you tighten it to 177 lb-ft. I have Toyota's MT and they sounded a bit loud. The bearings had some play but after installing the two front bearings the noise from the tires was significantly reduced which to me suggests the bearings were starting to make noise.