A precise “Jacobs type” chuck for use with chuck accessories having a diameter of 0.001" (0.03mm) to 0.25" (6.4mm). The 18 Atlas attaches to the right shaft of a dental lathe with standard dental tapered shafts. Machined to precision limits, the it provides the technician with concentricity unmatched by any other adjustable chuck with no run-out and no vibration. For right shaft only.Shipping weight: 1 Lb. (0.5 kg.)Unit dimensions: 2-1/2"L x 1-1/4" shank diameter (6cm x 3cm)