LT-500S tabs are suggested for use on V-bottom boats up to 24 foot not exceeding 65 mph. Measuring 12" long X 12" wide, these 1/4" billet aluminum tabs are competitively priced and are unmatched in quality. LT500 trim tabs are not designed or suggested for use on tunnel boat applications. Kits include (2) tabs, (2) billet cylinders, billet dash switch, pump, wire loom, lines, and fluid.