These drills are inexpensive spiral step drills. They have long lasting sharpness and are great for 1/4" hex drive. This allows me to use a bit of an extension cord to get into those hard to reach places. The drill bit's shank broke after a month of use (I use drill bits for the Fits school bus accessories, usually 1/8-1/4" steel), but the drill bit is still usable and comes at a relatively low price. I am happy with the purchase.