Silverline - GRADIENT LASER LEVEL (600MM) - 394965 A level that is not level at all. Each vial is set to indicate a gradient of 1°, 2°, 3°, or 4° from horizontal. If you have ever tried to lay a terrace with a slight fall across its entire length you will no doubt appreciate what a brilliant and simple idea this is. 600mm long with 6 vials. This clever aluminium level also features a built in laser making it ideal for setting gradients over long distances such as patios, guttering, drains, roofs & floors. Built in laser projects your chosen gradient up to 30m. Magnetic base. Milled bottom face. Includes 90° & line generating prisms. Requires 2xAAA batteries.