1-1/2" - 12 Gauge Smooth Shank Common Nail - 304 Stainless Steel, Pkg 228 Stainless Steel Deck Screws Although these are labeled as

Although these are labeled as drywall screws

Available in multiple lengths and sizes to meet a range of fastening needs

drives directly into pilot-drilled holes

This will only fit a post that measures an actual 12x12"

1-1/2" - 12 Gauge Smooth Shank Common Nail - 304 Stainless Steel, Pkg 228 Stainless Steel Deck Screws Although these are labeled asSimpson Smooth Shank Common Nail is available in type 316 stainless steel as well 304 stainless steel. 316 Stainless Steel is recommended for seaside applications and for superior corrosion resistance. Stainless Steel nails are recommended for construction of permanent wood foundations by the ANSI AF&PA Permanent Wood Foundations Design Specifications.