Compatible with both horizontal and vertical sliding windows For use with older style, metal framed windows For use with sliding windows that have a maximum of 3/16 inch thick frame fins Made of heavy-duty extruded aluminum with steel thumbscrew These sliding window thumbscrew locks come white in color Ideal for use as secondary security locks, often used for ventilating or securing windows in closed position No tools needed for installation Please refer to the line art and compare with your needs before purchasing