8 x 1-1/4'' Flat Head Square X Self-Countersinking Wood Screws, Lube Finished, 100-Pack - Rockler

Wood Screws - Boiseries Lussier

Centerline #8 x 2-1/2'' Washer Head Square X Fluted-Tip Wood Screws, Lube Finished, 100-Pack: : Industrial & Scientific

Workshop Tips Popular Woodworking

Screwdriver Bits - Drill Bits - The Home Depot

Tooth-like nibs under the head allow the screw to countersink itself- Square X head accepts both square drive and Phillips bits.

8 x 1-1/4'' Flat Head Square X Self-Countersinking Wood Screws, Lube Finished, 100-Pack - Rockler

Hillman 48255 8 X 1-1/4-Inch Square Drive Multipurpose Wood Screw, 500-Pack,Zinc, Wood Screws - Canada

Chris Schwarz Blog Popular Woodworking

8 x 1-1/2'' Oversized Washer Head Square X Wood Screws for Drawer Fronts, Zinc, 100-Pack - Rockler

Weekly Quick Questions, Wood ID, and Deal or No Deal /r/Woodworking Megathread : r/woodworking

Centerline #8 x 1-1/4'' Flat Head Square X Self-Countersinking Fluted-Tip Wood Screws, Zinc, 100-Pack: : Industrial & Scientific

8 Wood Screw, Flat Head, #2 Quad Drive, Deep Thread, Type 17 Point - Berenson

engineer-mechanical:machining - Jeffery J Jensen Wiki

Paulin #8-15 x 1-1/4-in Pan Head Square Drive Self-Tapping Sheet Metal Screws, Zinc-Plated

8 x 2-1/4 in. Zinc Phillips Square Drive Flat-Head Coarse Thread with Nibs Self-Tapping Double Auger (1000 per Box) 0.FCC08214ZN27 - The Home Depot

Robertson Drive Screws: Flathead, #8, 1-1/4 inch