1These pan head screws are great to use in confined areas where the head needs to be flush or below the surface 2Screws have sharp threads that cut into a material such as soft metal sheet, plastic or wood 3There are eight common lengths from 4mm to 20mmin this set for general purpose use 4Well packed and assorted in a resealable transparent box for convenient storage and carry 5Used widely in energy, electronics, electrical appliances, machinery, chemical, metallurgy, mold, hydraulic and other industries