Abstract: A removable laser base for a bubble level that includes a body, a laser beam generator, and a removable securement. The body has a flat top surface that the level is secured to and a bottom surface that is flat and parallel to the top surface. A laser diode mounted in a module emits a visible laser beam upon application of power from a battery that is controlled by a switch. The module, batteries, and switch are mounted in a through bore in the body. The laser base is removably secured to the bubble level by any manner appropriate to the shape of the level. In one such securement, the level has a T-shaped cross-section and the body has a complementary slot into which the level slides. When the level reference surface abuts the top surface of the laser base, a thumb screw is tightened to frictionally secure the level in the base.

Abstract: The level with a generally u-shaped or round, rigid frame. The outer surface is comprised of a number of planar reference faces that are at different fixed angles to a spirit vial mounted in the frame. Optionally, magnets are embedded in the reference faces. Optionally, there are grooves in the reference faces.

Abstract: The level with a generally u-shaped or round, rigid frame. The outer surface is comprised of a number of planar reference faces that are at different fixed angles to a spirit vial mounted in the frame. Optionally, magnets are embedded in the reference faces. Optionally, there are grooves in the reference faces.