This 15 x 28 x 13 mm (NA4902) bearing is a needle roller bearing. The NA4902 inner diameter is 15 mm, the NA4902 outer diameter is 28 mm, the NA4902 width is 13 mm.
Specs:
Inner Diameter (d): 15 mm Outer Diameter (D): 28 mm Width (B): 13 mm Bearing Model: NA4902 Material: GCR15 Bearing Steel