Absolutely the best hole saw on the market.  You will make your money back the first time you use this for your speaker installations. Adjustable Ceiling Hole Saw w/Dust Trap Cuts Holes 1-1/2 inch thru 10 inch in Diameter

53731 Klein Adjustable Hole Saw Cutter Perfect for Drywall and Ceiling Tiles Quickly and smoothly cuts cleaner holes in drywall and ceiling tiles. Blades adjust to cut holes from 2 to 7 in diameter. Fits most 3/8 and ½ drill chucks. No...