1)Laser Edge Level uses the latest Refractive Lens Technology to lay down a level 50 ft. Line. 2)- Adheres To Any Surface. - Hands Free. - Leaves No Marks. 3)The premium laser level that lays down a 50ft level laser line any surface! Get professional results on any home improvement project. Adheres to any surface, even tile, without leaving marks. Laser Straight is great for installing pictures, shelves, borders, towel bars, curtain rods, tiles, cabinets, and much more! Use it for just about any aligning needs you have.