5/16-18 x 4 Six Lobe Flat Floor Board Screw Type F Black Phosphate KPOHC They have a trim head

They have a trim head that sits flush with the drywall surface

The screw is RoHS compliant

Introducing the M10-1

this screw blends seamlessly into assemblies

It has a hex head with an indented drive for increased torque and a 1/4-20 thread size

5/16-18 x 4 Six Lobe Flat Floor Board Screw Type F Black Phosphate KPOHC They have a trim head5 16 18 x 4 Six Lobe Flat Floor Board Screw Type F Black Phosphate Size: 5 16 18 x 4 inches Material: Steel Finish: Black Phosphate Head Type: Six Lobe Flat Floor Board Drive Type: Type F Features: Six lobe drive head for increased torque and reduced cam out Flat floor board head for a flush finish Black phosphate finish for corrosion resistance Ideal for use in flooring, decking, and other wood to wood applications