Grey Tapcon Screws for Thresholds | Discount Door Hardware
Large Diameter Tapcons - Concord Carpenter
ITW Buildex 24292 Tapcon Concrete Hex Head Screw Anchors 5/16 By 2-1/4 Inch Blue 15 Pack: Concrete Anchor Screws - Hex Head Over 1-1/2 Pounds (092097242920-1)