Simpson #12 x 4" 316 SS Deck-Drive DWP Wood Screw, T27, Flat Head PACK:20 Pk shank diameter in a #8

shank diameter in a #8 size - balances strength and material compatibility for fiberglass

The Quik Drive system holds the screw securely as it drills through the metal joist for a more consistent installation

Blade Speed (SFPM): EVS 82-330

while the included ACU-RITE 203 three-axis DRO and X-axis powerfeed streamline setup and operation

What is the purpose of the coarse threads on only part of the shank

Simpson #12 x 4" 316 SS Deck-Drive DWP Wood Screw, T27, Flat Head PACK:20 Pk shank diameter in a #8Simpson Deck Drive DWP Wood Screw in #12 x 4" Type 316 Stainless Steel is a heavy duty fastener engineered for deck, dock, boardwalk, and general exterior wood applications where superior corrosion resistance is essential. Featuring a specially designed sharp point and unique box thread profile, this flat head wood screw drives smoothly into hardwood, engineered wood, and polymer decking materials making it a reliable choice for coastal, seaside, and