Maxx

There is another type of screw that is called a Maxx and has a square
drive socket for installation and can also be taken out with a philips
screwdriver.

It is supposed to be "self-tapping" in wood and "self-countersinking"
with "rills" under the head. It has a "lubricated" coating that is
also rust resistant.

http://www.robertsonscrew.com/product_4160.html

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