Comes with one HSS blade set and one Tungsten Carbide blade set.
Product Description: Twin blade user-replaceable, multi-functional hole cutter for cutting 1 7/8" to 12" holes. Don't be fooled by other 300mm hole cutters advertising they cut up to 12". Only a 305mm cutter can cut 12" holes. Comes with one High Speed Steel (HSS) blade set and one Tungsten Carbide blade set in a plastic carrying case. For replacement blades, order BH-002 (HSS) or BT-002 Tungsten Carbide.
Rating : - handy tool! I am a professional remodeling contractor and I install tubular skylights and own the 16" model. After some trial and error, I have found that a) you need to use the clutch on your drill to keep the binding action (that is inevitable) from hurting you. b) the blade positions do work well to set the hole size and keep everything centered - you just have to look closely at the markings, then check the total diameter with a tape measure. This tool is built extremely well and does a great job of cutting clean holes in drywall and plaster (haven't tried wood yet).
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