IRWIN Tools 2050 Magnetic Box Beam and Door Jamb Level, 78-Inch / 32-Inch (1794104) Continuous edge increases level durability to ensure accuracy over time, protects center vial bubble, and allows for continuous scribing. Plumb Site offers dual-sided, undistorted viewing in the plumb position and easy, more accurate plumb readings. Retractable end-caps allow for scribing into and through corners, increasing work efficiency. Rare earth magnets are 5 times stronger than strip magnets and allow for easy, hands-free steel construction work.