BC4Z-R, 4x4 Post Cap/Base Z-Max, Reduces The Chance Of The Post Splitting & Eliminates Nailing Into End Grain, Provides An Easy & Secure Connection Between Post & Beam, Made With 18 Gauge Galvanized Steel, Install With Three 16D HDG Commons Or 16D x 2-1/2" HDG Joist Nails Into Each Side On Surface A, Three 16D HDG Commons Or 16D x 2-1/2" HDG Joist Nails Into Each Side On Surface B, Total 12 16D HDG Commons Or 16D x 2-1/2" HDG Joist Nails.