This 25 x 42 x 17 mm (NA4905) bearing is a needle roller bearing. The NA4905 inner diameter is 25 mm, the NA4905 outer diameter is 42 mm, the NA4905 width is 17 mm.
Specs:
Inner Diameter (d): 25 mm Outer Diameter (D): 42 mm Width (B): 17 mm Bearing Model: NA4905 Material: GCR15 Bearing Steel