Overall Size: The outer square of the post plate connector measures 4.75" x 4.75". It is suitable for wood post of the standard of 3.5" x 3.5". Before purchasing, please werify the diamensions of your wood post and check the size sepecification(Picture 2) Protect Post Base: Designed for 3.5" wood post, this deck post base can be used to install wooden post on wood or concrete floor to protect the bottom of wood post or railing. Having a strong load-bearing capacity, this deck post base can withstand 250lbs without deformation Easy to Install: We have prepared M6 self-tapping wood screws and T30 drill bits in the package to help you install the connector easily. For more detailed installation steps, please refer to our installation diagram. For concrete floor, we recommend using M6 expansion screws High Quality: Muzata wood post plate is made of 45 steel(1045) and the connector surface is treated with black powder-coated finish, which has the performance of rust resistance and corrosion resistance, UV protection. It is not easy to fade and can be used indoors and outdoors Wood Railing System: You might need several wood railing kits to build a complete frame to enrich your deck railing system. Please search Muzata WT01 or WT12 for aluminum round or square balusters, WT33 for facemount wavy balusters, WT34 for facemount flat balusters, WT06 for wood post caps, WT08 for wood post plate, WT09 for one-piece post skirt, WT11 for deck railing bracket, WT16 for fence post repair, WT24 for split style post skirt