The Pulley PRO® belt alignment tool can measure spans up to 15 ft. (4.6 m) or better with any size pulley, large or small. A green laser line is projected from the Pulley PRO® transmitter to the reflector mounted on the opposite pulley. A reference line on the reflector indicates offset and vertical angle misalignment immediately. The laser line is then automatically reflected back to the transmitter’s reference line to show horizontal angle misalignment.