Can be used with concrete without a plug, and it can be easily installed with a regular screwdriver. Can be installed with various types of pipes saddle fasteners, switch boxes, curtain rails, storage shelves, air conditioning equipment, lighting fixtures, interior substrate materials, etc. Nominal diameter: d: 0.1 inches (4 mm); Bottom hole diameter: 0.1 inches (3.5 mm); Embedded depth: 0.8 inches (2 inches (2 mm); Compatible driver: 0 inches (2 mm). Shape: Pan Head Compatible Materials: Concrete, blocks; Mini pack; Stainless steel