5/16-18X2 Six Lobe Pan Floor Board Screw Type F Fully Threaded Black Phosphate, Pkg of 500

6X3/8 Phillips Full Contour Truss Self Tapping Screw Type B Fully Threaded Black Oxide. Type B thread for molded or through holes in thin metal, non-ferrous castings. Truss head screws are weaker than pan or round heads but preferred in applications where minimal clearance exists above the head. Modified truss heads offer low clearance and an extra large bearing surface. Commonly used to attach metal lathe to metal studs.

1/4-20X2 1/2 Six Lobe Flat Floor Board Screw Type F Black Phosphate. Thread-Cutting Type-F threaded screws are used in heavy gauge sheet metal, aluminum, zinc and lead die castings, cast iron, brass and plastic. In stainless steel, material into which the screw is to cut threads should have a lower hardness by 10-20 Rockwell hardness. Flat head screws are used when protrusion of the fastener above the mating surface is unacceptable. Typically 100 degree flat or for fastening softer materials, 82 degrees flat.

1/4-20X3/4 Phillips Round Machine Screw Fully Threaded Black Oxide. Machine Screws are designed to go through a hole or nut that is pre-tapped to form a mating thread for that screw. Round head screws are sometimes perferred over a pan head for its smooth surface and appearance.

8X2 1/2 Square Recess Drive Bugle Head Coarse Thread Drywall Screw Black Phosphate. Bugle head screws are commonly used for drywall because it distributes bearing stress over a wider area than a flat head.

8X1 Square Drive Bugle Head Fine Thread Drywall Screw Black Phosphate. Bugle head screws are commonly used for drywall because it distributes bearing stress over a wider area than a flat head.