... : SCM440,42CRMO,15CRMO,25CrMo LENGTH:3M-6M We can supply the guide rail,if you require this ,please contact me,send me ... the drawing ,thanks!Guide ( daogui ) guide rail: metal or other material groove or ridge ... mobile device or equipment and reduces the friction of a device. Guide on the surface of the longitudinal grooves or ridges, used for guiding ...