Stanley Magnetic I-Beam Aluminum Level Size: 24″ (43-554) & 48″ (43-556) Accuracy: 0.58 Degree/0.001″/1.0mm/M Shock Absorbing End Caps Extra Large Vials for clear visibility Durable Aluminum frame with precision milled edge Heavy-duty aluminum I-beam construction for strength and long service life Magnetic base for convenient hands-free leveling on metal surfaces Three tubular vials for horizontal, vertical, and angle measurements Clear, easy-to-read vial design for improved visibility Top-read center vial for convenient viewing from above Shock-absorbing end caps help protect the level during demanding use Continuous working edge provides a smooth surface for marking Suitable for construction, fabrication, carpentry, installation, and maintenance work