An adjustable how saw/hole cutter suitable for professional or occasional use. Simple to use fully adjustable design allows you to set the exact size required for the job. Fits into any drill electric or air. Manufactured from chrome vanadium steel. Shank diameter 10mm Will drill a hole 30mm to 120mm diameter. Blade length 25mm. Comes with brad point for thin sheets or drill for thick boards. Simple to adjust, simply slacken the grub screw with an Allen key (supplied) then tighten in the desired position. Maximum thickness that it will cut; 30mm. Graduated in metric and AF (inch) sizes just slide along the bar either side and select the scale that you require. Cuts the following material : Plywood / Laminates / Composite boards / ALC / Gypsum board / Plastic / Rubber and numerous other materials. Not suitable for use on metal.