With no hydraulics and no electrical switches, fully automatic Smart Tabs are a one of a kind solution to improve boat performance. The trim plates deploy downward at slow speeds to maximize lift and reduce bow rise, then rotate up during acceleration. At cruising speeds the trim plates continuously adjust to the water pressure acting like shock absorbers to improve stability, eliminate porpoising and chine walk at high speeds, and reduce fuel consumption. Installation can be completed in less than one hour. Features all stainless steel components, self-contained nitrogen gas actuators sealed with EDPM rubber boot, complete installation instructions and owners manual. 5 year metal component, 2 year actuator warranty. Size 12" x 9" Boat Size 17'-21'+ Application 80 to 150 hp / 2 or 4 stroke / 4 or 6 cylinder I/O Actuator 60 lb.