Abstract: An isosceles triangular plate with depending flanges on its two equal sides is provided, adaptable for mounting under kitchen or galley shelves or cabinets for the purpose of loosening and tightening screw-type lids or caps of jars, bottles, and the like. A resilient rubber gripping bar is fixed to said triangular plate and bisects the angle between said flanges. Screw type closures are loosened or tightened by their insertion on the appropriate side of said bar and rotated clockwise or counterclockwise respectively. The camming action of the flange serves to wedge the lid more tightly against the rubber bar, thus increasing its gripping force.