THK Precision Linear Pack model ER is a slide unit using a stainless steel plate that is precision formed, heat-treated and then ground. It has a structure where balls roll between the V-shaped grooves machined on the outer rail and the inner block to allow the system to slide. THK precision linear pack model er is an ultra-thin, lightweight unit in which the balls circulate in a ball case incorporated in the inner block to perform infi nite straight motion. This model is used in extensive applications such as magnetic disc devices, electronic equipment, semiconductor manufacturing equipment, medical equipment, measuring equipment, plotting machines and photocopiers.