SMSFC6GUU NB Center Mount Round Flange Slide Bush Made in Japan:NB Linear Systems Nippon Bearing Linear Systems SMSFC6GUU NB Center Mount Round Flange Linear Slide Bush, Bearing is anticorrosion, Bearing is seals on both sides , The retainer material is resin, series mainly used in the USA, NB brand (Nippon Bearing Linear Systems), Made in Japan.