6-Lobe Drive Flat Heads (Floorboard)
		G		T	B	F
Nominal Size or Basic Screw		Head Dimensions			Recess Dimensions
Diameter							Drive Size
		Max Sharp	Abs. Min	Ref	Ref	Gauge Penetration Min
1/4-20	0.2500	0.520	0.452	0.160	0.221	0.060	T30
5/16-18	0.3125	0.648	0.568	0.199	0.266	0.090	T40

Description	A countersunk, 6-lobe drive thread cutting screw with machine screw thread pitch, blunt point, tapered entering threads, and multiple cutting edges.
Applications/ Advantages	Floorboard screws are specifically designed for installing wood floors into truck trailers or wood to the interior of containers.
Material	AISI 1016 - 1024 or equivalent steel
Heat Treatment	Screws shall be quenched in liquid and then tempered by reheating to 650 degrees Fahrenheit minimum.
Surface Hardness	Rockwell C45 minimum
Case Depth	.005 - .011
Core Hardness (after tempering)	Rockwell C28 - 38
Thread Dimensions	Same as those for Type-F thread cutting screws.
Plating	Black-Phosphate