- 1/4"-1-3/8" M2 Step Drill Bit Unibit for Hole Drilling 5 Sizes

This works great. Used on heavy stainless pipe to make a large hole no problems.

Good drill bit for the price and works great.

Very good step drill, but I was surprised that the 1/4-1 3/8" model didn't have 1" as one of its steps. My fault for not reading more carefully.

A must-have in any good toolbox.

Went thru and spent a lot of time trying to drill thru a SS Sink flange to no avail using traditional tungsten and carbide bits (over an hour). Was looking for alternatives when I came across this. I have never used this type of bit. So I decided to give it a try and kill two birds with one stone. To my amazement, it cut thru the SS flange like butter. In less than a minute it made the hole. Worth every penny. Can't say enough how impressed I was, and it is still sharp.

amazing tool. after attempting to make a machine looking tool....other cutters made a sloppy cut. This tool makes an elegant bore where appearances count

Extremely aggressive and sharp bit which grinds out holes in metal quickly. Very impressed.

Bought a kitchen sink ar Costco recently lacking a 1 3/8" soap pump hole for a undercounter sink mount for our new granite countertop install. When the guy came out the measure, I found out that they had a policy for liability reasons of not drilling holes in costumer sinks. I wanted the sink and wanted the pump, so I said I would find a way to drill the hole. I read a lot of reviews on Amazon for step hole drills and found reviews that that had some praising the drill's performance on stainless steel while others saying that the drill never worked. I looked at the design of the drill and figured out what the problem was. Stainless steel is very hard (several times harder than sheet metal) so getting started is a separate process. The trick is to first drill a small diameter pilot hole using carbide tip drill bits and, once started, increase the diameter, one size at a time, until you get to about a 1/4" diameter. Then use this step drill. Take your time, don't make the mistake of drilling at high speed because the high heat friction can make the SS metal even harder, and get milling oil (Amazon had some for less than $5) to keep the friction heat down. If the drill site starts smoking, it's usually the milling oil burning. Stop immediately, make sure the bit cooled down, then apply more oil before starting again. Take your time and you will be surprised how well it works.

Bought this bit to make a hole in my stainless steel sink. It worked very well! Would recommend buying it.