Features - Requires two AA batteries (Not Included) - Twin Push Pins Allow Quick And Accurate Attachment To Many Surfaces - 2 Leveling Vials For Both Horizontal And Vertical Positioning - Special Lens Which Allows Line Continuity Over Imperfect Surfaces Such As Dado Rails, Mouldings,And Trims - Ideal Use For Applications Where An Accurate Line Is Required Example Laying Conduit, Copper Piping, Tiling, Shelving And Decorating