2 Inch / 50mm Diamond Drill Bits, Diamond Hole Saw Hollow Core Drill Bits for Glass Ceramic Porcelain Tiles Marble Granite Quartz

Cut two 2.5 inch holes in travertine. Did a good job. Make a dam with plumbers putty to hold a small amount of water to cool the bit. Start cut on a angle to avoid bit walking away.

I tried using carbide bits and had limited success. These bits worked GREAT!!

My four star rating is based upon cost vs performance which is often not qualified. I needed to drill (4) 2" diameter holes through 1" thick granite. It did the job which was why I bought this particular drill bit, that being a one time use. I'm a contractor and weigh cost & performance all the time.

I spent $100 on 6 bits from two different box stores and barely made it through 5 holes that took 5 hours to drill in porcelain. I took a chance on these 5/16" bits and were they worth it! I bought two orders thinking I would need all of them but I was wrong. One bit made it through in one minute and drilled multiple holes. Buy them!Update!Bought the 4 1/2" hole saw, works just as great as the 5/16" bits!

three cuts and it no longer has a sharp edge, the last cut was made with a lot of effort.

Had to drill 5 holes in a glass sheet. Actually did it in less than likely 5 minutes of total drilling time.I did us blue tape to make little dams for water and added some Diamond Coolant I use for stain glass grinder too.Did get some break on an slight cracking on first whole, pushing to hard. All other fine.As stated in one of the others start on edge, using variable speed drill, then speed up an start laying down and it will go to full circle. Not sure if full speed is needed or best.I had only one shot, but if you can do some tests first would advise.I was able to repair chipped and minor cracks with some two part epoxy and even did a little water type effect. It is a special project for an Aquarium.

It works great when it comes to cutting. Starting a hole is cumbersome as the unit does not come with a center bit where you can insert a drill-bit - thus you have to have it spinning when you put it to a wall, for example - and THEN you better hope you are centered! I had to drill holes through my wall for mini-split air conditioner, so I did it from the inside with a longer concrete bit, thus you have a center from the outside, BUT without this unit having a center bit unit, it is "guessing" you are center from the outside. I did NOT get them center - but I got it kind of close - THUS I CANNOT recommend this product. That's why I gave it 4 stars, which is actually one too many in my opinion!

I purchased this diamond drill for my new quartz desk top. The desktop needed four holes drilled to accomodate a decorative wire feature that mounts inside the hole. I gave the drill to my Quartz installer hoping it would work as he did not have this size. Much to his surprise the drill made a perfect hole and the decorative feature fit perfectly. Great buy for the price.

Absolutely would buy again! Great price and works perfectly - low speed and use water to cool

Funcionan bien. Hay que utilizarlas con mucha lubricación. Aun así practicamente son para una o dos ocaciones maximo.

Way easy to use and precise, in cutting a circle. I recommend it for pros or handyman. Makes a clean cut with little chipping because diamond chips are on both inside and out of the cutting edge.

Para quitar el fondo a unas botellas de vidrio, muy funcional

Llego a tiempo, aún no la uso pero se ve bien la pieza que también llegó en buenas condiciones. Solo que decía en la descripción que el paquEl precio es dete tenía 12 piezas pero solo entregan una, no obstante el precio es muy bueno por una pieza.