Length: 1000mm The shaft is case hardened. If you use normal steel shafts, the bearings will cut them up in no time. So make sure what you buy is case hardened! Aluminum support rail with pre-drilled holes for ease of mounting Perfect for your DIY CNC routers, mills, lathes For 12mm slotted bearings Suits X, Y, Z axis No more unwanted errors in your machining work! All items located in China , but you will get it fast and packed well! Don't risk having it shipped from overseas! These rails are also available in diameters of 16mm, 20mm, 25mm and 30mm Brand new! Please check out my other CNC items & we do provide combined shipping! We also sell the matching bearings to suit this shaft! Please click the following link: 12mm slotted bearings for linear rail     Package: 2 x SBR12--1000 mm Rail Support 4 x SBR12UU