Inside corner posts are used at the inside corners of a wall, where the siding meets from two adjoining walls. The inside corner post provides a weather-resistant joint with the siding fitting neatly in the channels. Generally the color of the inside corner post matches the siding used for a uniform look, but can also be a contrasting color as well for a distinguished look.

Outside corner posts protects corners and has a receiving channel that hides the ends of siding panels for a finished, professional vinyl siding installation.