14 x 3 1/4 Simpson Flat-Head Self-Drilling Screw w/ Wings - Square Drive 410 SS - Box (100)

14 x 3 1/4 Simpson Flat-Head Self-Drilling Screw w/ Wings - Square Drive 410 SS - Box (100) .

• Fasten wood, plywood and fiber cement to heavier steel – up to .209" thick
• #3 square drive
• Machine screw thread, threaded full length
• 2 1/2" length for 2 x 4 wood header; 2" length for 1" and 3/4" boards
• Flat countersunk head with self-countersinking nibs
• Shank slot enhances thread formation in steel and removes exhaust
• Wings above drill point provide clearance hole in work piece so it won’t climb up the shank, then break off as point engages the steel substrate
• Drilling thickness capacities: up to .209" (171 mils, 7 ga) for #12, up to .250" (229 mils, 3 ga) for #14