Miniature linear guideway

A linear guideway, comprising:

• a rail;
• a slider slidably arranged on said rail, said slider comprising a middle portion and two side portions connected to two opposite sides of said middle portion;
• at least one circulation fitting slidably disposed on said rail and connected to said slider, so that said at least one circulation fitting forms a circulation channel between said rail and each of said side portions of said slider, said at least one circulation fitting comprising a plurality of turning convex portions, wherein the plurality turning convex portions are spaced apart on said at least one circulation fitting;
• a plurality of balls located in said circulating channels;
• and
• a retainer comprising a plate portion, a plurality of positioning portions and two retaining portions, said retaining portions each having two ends and each end is connected to said plate portion by one respective said positioning portion, said plate portion of said retainer being adjacent to said middle portion of said slider, said positioning portions of said retainer abutting against said turning convex portions of said at least one circulation fitting, each of said retaining portions of said retainer abutting against said balls, wherein, the width of said plate portion of said retainer is smaller than a distance between said turning convex portions of said at least one circulation fitting.