The Hardin GPD1-JH55 has been developed through necessity; taking a difficult yet essential job and making it effortless. This gas powered pile driver pounds star posts in the ground quickly and efficiently. Not only do you save on labor and time but you save your elbows, back, and hands! Just thread the appropriate size cup onto the business end of the Hardin GPD1-JH55 and get those posts into the ground. Driven by the powerful G95 2-Stroke 32.7cc engine this tool is economical as well as efficient to run. Made from the highest grade materials throughout. There has been no compromise in quality in any aspect. This comes with 2 different size cups that thread onto the business end of the driver. They are both 6 1/2 inches long. The ID is different. One cup is 2 3/4 inches ID. The other is 1 15/16 inches ID. This allows different size posts to be efficiently driven into the ground.