... .1. Compozition: rail, slider, ball, back to the browser, dust cover, Cage, isolation chain.2. Features:(1)High efficiency, the ... the use of automated enforcement oil supply mechanism.(6). Dust cover with the second dust-proof, dust-proof better.(7). Isolated chain, thus increasing ... . Users to choose from, adapt to working environment and more dust. (10). Overweight set type, set type has RIT-LA, ...