CHECKPOINT 400 Ultra Mag Laser Base V-Groove bottom to fit radius pipe and conduit work 4 Neodymium rare earth magnets to add incredible magnetic strength Ultra Mag laser base is CNC machined from Billet 6061 aluminum alloy Color buff polished and aircraft anodized with permanent laser engraving Compatible with the following Checkpoint levels; part no.300 Ultra Mag torpedo level part no.305 Mega Mag torpedo level part no.303 Ultra Mini Mag torpedo level