Steel Thread Cutting Screw， Black Oxide Finish， 82 Degree Flat Head， Phillips Drive， Type F， #4-40 Thread Size， 3/8" Length (Pack of 100)<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Thread cutting screw with type F point has machine screw threads that taper down to a blunt edge and is suitable for heavy gauge sheet metal， aluminum， cast iron， brass， and plastic</li><li>Steel is often used in applications where strength is the primary consideration</li><li>Black oxide finish offers mild corrosion resistance and lubricity</li><li>Flat head has an 82-degree cone-shaped bearing surface for use in countersunk holes and a flat top that fits flush with the mated surface</li><li>Phillips drive has an x-shaped slot that accepts a Phillips driver and is designed to prevent over-tightening</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41IjGGI1pDL.jpg" noproxy>