48, Magnetic, Heavy Duty Aluminum IBeam Level, Strong Holding Magnetic Edge Allows Hands Free Use On Ferrous Metal Surfaces, Oversized 12 Diameter Vials Are Easy Read, Job Site Tough, Ergonomic Cushioned Hand Grips, Surround View Vials Reflect Ambient Light For Easy Read, Top Read Window Maximizes Readability, Durable Protective, Field Replaceable, Acrylic Cover Plates Protect Vials From Weather Dust, Shock Absorbing End Caps Protect The Frame When Dropped