Vertical mixing action blends materials from top to bottom. Made of nickel-plated steel. For use with a variable speed,reversible electric drill. The unit's shank is easily clamped into a 3/8" or 1/2" chuck drill as an ordinary drill bit.30" long, 4.8" diameter, 1/2" hex shank, 5 gallon drywall mud and low to medium density materials.