Uflex Mechanical Hatchlifter 12" STK Fast [AV3012]Mechanical Hatchlifter 12" STK Fast The AV hatch lifters are electromechanical products, especially designed for marine use on pleasure boats. They allow full or partial opening and closing of heavy engine hatches, peak tanks, hatch beams etc. By activating a switch, it is possible to lift the hatch to any desired position from closed to full open; an internal self locking mechanism will maintain the position preventing any accidental hatch closing.