We have these (4" and 1" 2 each) for planting shrubs, flowers and small trees. We had 3 boxwood plants that needed planting in the garden and the rest died from frost in Texas. I put a 4" on my 18 volt cordless drill, cranked the torque to maximum and in less than 8 minutes all the bushes were planted. It was really easy: stick tip in the ground, turn on drill, drill lower (and he had to go through some loam because of our soil type, and he went through the loam with no problem), dig loosen soil, plant plant, cover roots with soil and DONE! I think the attachments on these stand out from most different from others sold at Revain make a big difference, they are durable and due to their design they fall right into the ground.