1MAIN FUNCTION: You can quickly and permanently mark your connection points in construction sites, halls, or other buildings. Reflection markers are developed for measuring buildings or terrain using a tachometer. 2EASY TO VIEW: Due to the small coverage of the target, the reflective surface on the target is clearly visible. 3PREMIUM REFLECTIVE TARGET: Made of thin film, placed on a panel made of anodized aluminum for better visibility. 4WIDE APPLICATION: Widely used in various industries such as subways, railways, tunnels, dams, steep slopes, etc. 5ABS MATERIAL: Made of premium ABS material, this reflector is wear resistant and scratch resistant, withstanding different tunnels environments, use with confidence!