Simpson 5d 1 3 4" x 0.083 Wood Siding Nail, 304 Stainless Steel Cold Formed Steel Connectors The 18" overall length with The 18" overall length with a 16" working length gives access to deep embedment depths required for anchor setting in thick reinforced concrete slabs and walls Slit design allows the insert to pass through while containing the adhesive in the hole keeps adhesive exactly where it needs to be during rod or rebar insertion Annular ring shank design significantly increases withdrawal resistance compared to smooth shank nails Type 304 stainless steel construction makes these nails well suited for exterior wood siding exposed to rain