Dottie Square toggle bolt has type UNC thread of size 1/4 - 20. It measures 3-Inch x 1/4-Inch Dia. Spring wing toggle bolt features Phillips/slotted drive and has 20 TPI. This toggle bolt is light to medium duty anchor for use in hollow walls. Mushroom head of this toggle bolt offers large bearing surface. It has durable steel construction with zinc-plated finish.