... . There have four types are available, OPEN type (No shields), ZZ type (Metal shields), 2RS type (Contact rubber seals), 2RZ (Non ... ball bearingBrand nameW QSeries6300 seriesMaterialChrome steel (Gcr15)OriginalChinaSealingOpen, Shield(Z, ZZ), Rubber(RS, 2RS)SamplesAvailablePrecision RatingP0,P6,P5Quality StandardISO9001:2008, ABEC1 ...