Koopi 4.25 Hole Saw with Heavy Duty Arbor, 38mm Depth Bi-Metal 4 1/4 inch Hole Cutter for Easily Drilling Wood, Plastic, Plywood, Drywall, Thin Metal (108mm)

I needed the 6 3/8 hole saw to install a duct for a range hood through four kitchen cabinets. The Koopi is a heavy duty unit, accent on heavy, and the one I received seems round and well balanced. Learn-by-doing experience: I found that my 20 volt Dewalt drill is adequate for this saw, but I wouldnt want to use anything smaller. The saw is unwieldy to use, especially in the top of a wall cabinet where keeping the saw parallel to the cutting surface is a challenge. Using the drills clutch to keep the drill from spinning dangerously when the teeth bind in the wood was the only way I could manage it. This way when the saws position isnt just right the drill clutch engages; when the hole saw is correctly placed the teeth do their job fairly well. It did take some time to cut each 1/2 inch deep hole--and my high end Dewalt drill got very hot--but the saw worked well. Ive cut seven plywood holes so far and the saws teeth dont seem too worn yet. This is a pretty good tool for something I only need for one job.

Its not crazy high quality, but if youre a DIYer putting in some wafer lights, it will do the job without falling apart. Pro tip: run it in reverse to keep your drywall cuts clean and dont push too hard.

Sawed over 100 holes thru wood for a ice-cream cone craft stand. Worked perfect.

Good value, came with spindle and an extra center bit which is really nice. Seemed to clog a little faster then some of the name brand hole saws I have in my collection but did an adequate job of cutting. Didnt cut all the way through so unsure of how hard it is to remove the cut out piece only has small slots for that purpose. All in all excellent price and fast delivery.

At a large hardware store this will cost you over $30. Here it was a fraction of the cost without compromising the quality. I was installing a laundry exhaust and had to cut through aluminum siding asphalt siding and plywood for a total of 3 inch thickness wall. I did have to do it in increments because of the depth of the hole saw but that is to be expected.

Ordered this hole saw to install ceiling cans. It works great on the first three. After that It dulled quickly.

I HAD 50 LIGHTING ADAPTERS TO MAKE THAT I NEEDED TO MAKE A 6-3/8 HOLE IN 3/4 PLYWOOD TO INSTALL A WAFFER LIGHT IN , AND A SKILL SAW WAS GOING TO TAKE FOR EVER. SO I OREDRED THE HOLE SAW AND MADE A FIXTURE TO HOLD THESE IN A DRILL PRESS AND THE SAW DID THE TRICK SLICK AND EASY, QUALITY WAS GREAT COMPAIRED TO HIGH PRICED UNITS IT COMES WITH 2-DRILL BITS AND THE HOLDING ADAPTER AND HEX WRENCH, WOULD BUY AGAIN!!!

everything

This is sturdy. Good welds.

This worked well for cutting out holes for my can lights. The hole saw is much heavier than I thought and the the peg holes on the side are very much needed to keep the center from slipping/stripping while you drill. Some other brands offer a spring on the bit to kick out your wasted center but at least for my drywall, this wasnt an issue. I could see this being a slight pain with wood but not a deal breaker. A few downsides however is that when you thread your drill bit assembly, there is still 1/16 or so that you could tighten to get it to seat completely BUT then the side pegs wouldnt be able to seat in their respective holes so youre left with backing it off a bit. One thing I was not expecting that you should be aware of when cutting something more heavy duty like wood is that due to its weight, this thing will act like a car flywheel and have enough inertia to kick out your drill so I definitely recommend double hand holding your drill or better yet, using one with a side thread handle.