NB SW48AJ 3 inch Adjustable Ball Bushings Linear Motion 8029. This product data sheet is originally written in English. SW48AJ:Clearance Adjustable Type Ball Bushing Made in Japan:NB Linear Systems. 3" SW48AJ Clearance Adjustable Type Linear Motion Ball Bushing, 3" Bore inch type linear motion ball bushings/bearings, inner diameter(bore) is3 inch, high accuracy grade linear bushings, inch series is mainly used in the USA, NB brand (Nippon Bearing Linear Systems), made in Japan. Type: Linear Motion Ball Bushing.Size: 3" x 4 1/2" x 6 inch. Outer Diameter: 4 1/2 inch. The NB slide bush is a linear motion mechanism utilizing the rotational motion of ball elements. Since linear motion is obtained using a simple mechanism, the slide bush can be used in a wide variety of applications, including transportation equipment, food processing equipment, and semiconductor equipment. The NB slide bush uses a round shaft for the guide, resulting in effective space utilization, which allows for compact designs. The raceway surface is precision ground. Since the contact surface between the ball elements and the raceway surface is minimized, the NB slide bush provides low friction when compared to other linear motion mechanisms. Major dimensions and tolerance (inches). Since the contact surface between the.