SMSK8WUUE NB Square Flange Double wide Pilot End Anticorrosion Slide Bush Made in Japan:NB Linear Systems SMSK8WUUE NB Square Flange Double wide Pilot End Linear Slide Bush, Bearing is anticorrosion, The retainer material is resin, It is seals on both sides, series mainly used in the USA, NB brand (Nippon Bearing Linear Systems), Made in Japan.