Kritter Caps are designed to fit inside the corner posts of a vinyl-sided structure to stop mice, rats, snakes, bees, wasps, hornets and other pests from entering through an open corner post. The SCI-354 combination Kritter Cap is universal and can be used on 2.75-, 3-, 3.5- and 4-in. corner posts. It is easily sized by snipping or breaking off sections with side cutters or pliers. The base filler tabs are used for filling voids where the plywood sheathing or insulation under the siding doesn’t come to a square corner, and can be removed if not needed.