This precision tool is used by toolmakers to mark a perfectly straight and parallel line at the exact height required. Excellent for marking scale ship model waterlines and for transferring gunport, porthole and other item locations from the ship's plan to the hull. Can also be used for marking-out raised panels, windows, chair rails, etc. in dollhouse construction. Adjusts quickly to approximate location with coarse adjustment knob and then to exact location with fine micrometer type adjustment knob. Measures and marks any height from 0 inches to 10 inches. Made entirely of steel with ground and polished base and needle sharp scriber. Can also be used with a pencil.