1Wide Use: Seat angle adjuster is suitable for RVs, trailers, trucks, construction vehicles, modified vehicle seats, etc. 2Multi Angle Adjustment: The seat back adjuster can be flexibly adjusted from 0 to 180 , users can choose the most suitable sitting angle according to their own preferences and needs. 3Comfort Enhancement: By adjusting the angle of the seat back, you can change the posture and support point of your body, thus enhancing ride comfort. 4Strong Support: Seat angle adjusters are made of high strength materials with sturdy construction and reliable support for increased ride safety. 5Durable Material: The seat back hinge recliner is made of high grade heavy duty steel for rugged durability and has a black painted exterior to resist oxidation for long lasting durability.