This is a set of auger bits to attach to your cordless drill (3/8") at home. The different lengths and diameters are key to being able to use them for a variety of applications. For example, the large diameter is good for planting flower bulbs or for example creating holes for a volleyball net. Smaller diameter snails are suitable for seeds, or in my case i used it to create holes for mounting solar street lights (like small poles). The possible applications are extensive. Caution: When drilling soil with roots or larger rocks, go slowly and carefully before freezing, a lot of torque is suddenly applied to the wrist. I usually press the drill against my knee for some support and leverage so my wrists don't take all the load.