Mode l : MGN12H. Length: 250mm / 9.8in, 300mm / 11.8in, 350mm / 13.8in, 400mm / 15.7in, 450mm / 17.7in, 500mm / 19.7in, 550mm / 21.7in (Optional ). Slide t rack: Linear rail. Slide block is designed with mini retaining steel wire, and the steel ball will not fall off if taking the slide block down.
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