SMSF8WUUE NB Round Flange Double Wide Type Miniature Anticorrosion Slide Bush Made in Japan:NB Linear Systems SMSF8WUUE NB Round Flange Double Wide Miniature Linear Slide Bush, The retainer material is steel, Bearing is anticorrosion, It is seals on both sides, series mainly used in the USA, NB brand (Nippon Bearing Linear Systems), Made in Japan.