BUILT TO LAST: Constructed of heavy-duty steel, with gloss black painted finish. The tip of the auger bit hits the ground first and keeps it stable when digging hard ground. Our patented design also makes the distance between the start of the digging blade and the point is minimal, so the auger bit will start working on hard ground without having to push down. Size: 8mm steel shaft with non-slip hex drive. 0.3 inch (8mm); 10cm in diameter x 30cm in length. Quickly digs holes up to 12" deep and 4" wide using the power of your hand drill. SAVE YOUR TIME & EASY TO USE: Our earth drill bit will work with any 3/8 or larger chuck drill, 18V or larger drill recommended. Plant hundreds or just a few bulbs in minutes. For cordless drills, a minimum 14V drill is recommended; Keep the auger clean of soil and debris when not in use. Multi-Purpose: Our spiral hole drill is the best choice for landscapers to increase efficiency when planting bulbs, potted plants, vegetables, flowers, bare root