Versatile Use - - The wood hole saw allows you to drill through plywood, woods, plasterboard, acrylic, fiber cement boards, etc... Adjustable Diameter - - The adjustable drill bit is capable of drilling large diameter holes (from 30mm to 120mm) to be able to mount spotlights or recessed speakers for example. Material - - The adjustable drill bit is made of chrome steel -vanadium, anti-corrosion, anti-combat, anti-bending and reused after grinding. Advantage - - The tool has a real advantage in terms of drill diameter adjustment thus avoiding the collection of hole saws. Note - - Before drilling, make sure the 2 styli are adjusted to the same diameter and the initial rotational speed is not high. Product description Features: For drilling plywood, plasterboard, acrylic, fiber cement boards, etc... Ideal for air conditioning pipes, fans, ceiling lights, in-ceiling speakers Allows you to drill holes 30 to 120 mm deep. Drill mounting Hexagonal shank with 6 points Specification: Material: