Sun Company Lev-O-Gage Boat Clinometer. Monitors tilt angle from -45 to 45 degrees. Mounts to the bulkhead with included high-bond tape (no hardware required) and aids in trimming sails for optimal speed. Large size and engraved/hand painted numbers make for a functional, easy-to-read display. Sturdy ABS plastic housing. Brass indicator ball rides in special damping fluid. Saturn yellow tube assembly is made of special shatterproof copolymer. Made in the USA. 3.5" x 1.6".