This is used to provide a flat surface to pound a 4×4 into the ground with a sledge hammer. The 4×4 should be pointed on the bottom. 1″ thick Steel on top and 3/16″ wall thickness on the sleeve.
This part is expected to wear out over time because it absorbs the blows from a sledge hammer. This is a wear part.
We recently changed the size of the cap so it will now fit over a rough cut 4×4 post. It is now made with 5″x5″ tube. Inner Dimension is 4.5″ x 4.5″