Metallics Combo anchor spring wing toggle bolt features steel construction with zinc chromate finish for superior corrosion resistance. This UNC bolt has thread of size 1/4-Inch and 20 TPI. It measures 3-Inch x 1/4-Inch Dia. Round headed bolt has slotted/Phillips driver. It has drill size of 1-1/4-inches and tensile strength of 310 lb for 1/2-Inch wallboard. This bolt is perfect for light-duty anchor for use in hollow block and gypsum wall.