NB Systems SW4 1/4" inch Ball Bushings Linear Motion
SW4:Made in Japan:NB Linear Systems Nippon Bearing Linear Systems
SW4 1/4" Bore linear motion ball bushings/bearings, inner diameter(bore) is 1/4" inch dimensions with steelretainer, Bearing is a high accuracy grade linear bushings,series mainly used in the USA, NB brand (Nippon Bearing Linear Systems), made in Japan.