The high precision linear scales is specially designed, precision, high speed, stable and accurate. The signal line adopts multi-layer isolation steel and metal soft shell protection, waterproof and anti-interference fine. Easy to install and maintain, waterproof, dust-proof good, long service life. Widely used, high stabilization, capacity of resisting disturbance well. Suitable for JC800 data display instrument. Type: Grating Electronic Ruler. Linear Scales Size: 53.53.32cm/21.11.30.8inch. 1 x Linear Scale Set (400mm). Please allow slight error due to manual measurement. Thanks for your understanding. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. We will reply your message within 48 hours. If you do not receive our reply within 48 hours, pls. Post a message again because sometimes our message system may block some emails. If you are satisfied with our service, pls. Our aim is to provide Level Customer Service, your recognition will encourage us greatly and serve you better. We strive to keep all our customers satisfy. We will do our up most to exceed your expectations in customer service, communication and dispatching of your orders.