http://www.constructionfastening.net/Tapcon_Screws_s/112.
Tapcon Anchors are known by many names, concrete screws, the blue screw, blue concrete screws and on and on. Whatever you call them, they are a great anchor for use in poured concrete, block and other masonry materials. We stock the original Tapcon screw in lengths up to 6" along with bits and install tools and a full line of concrete anchors and other specialty tools and fasteners. Check them out at htm or call us toll free at 1-877-212-2377.
http://www.itwredhead.com/pdfs/submittals/Tapcon_Orig.pdf
