4-inch auger with Pengo style pilot bit. For all soil conditions. Ground Hog is leading the industry with their 7/8 in. square auger drive that they have been using for over 50-years. High quality, heavy-gauge, welded steel construction provides for an auger that is durable. Their augers are designed to be used on all Ground Hog earth drills that have the 7/8 in. square auger drive.