1. Appearance: Look at Four corners of the profile is compact and light, the incision is smooth (PS: Professional cutting machine cut out clean and smooth) Another poor quality profile color oxidation is not very good, with the naked eye can be distinguished.
2. Open profile with hand touch, contrast profile thickness.
3. Look at the side of the panel and the guide plate is smooth and do not cut the hand, high-quality light box plate is carved using laser engraving machine, there will be no cut the situation.
4. Brightness: Check the brightness of the light box is uniform our all guide plates are based on optical principle using dot screen printing method to process, so that the minimum optical difference.