Knoweasy 3Pcs High-Speed Steel Step Drill Bit Set (4-12mm/4-20mm/4-32mm) - Multi-Size Hole Cutter for Metal, Wood, Aluminum & Plastic - Perfect for DIY Projects, Home Improvement & Professional Metalworking

I bought this bit set to drill panel holes for electrical conduit installation. I only required the 1/4 to 1 3/8 bit, but the price for 5 was 1/4 that of the single bit so I took a chance and am pleased to report I was not disappointed. The performance of the bit I used was on par with the professional bit I've been using for smaller holes. There was no deterioration in the cutting edge nor visible wear to the coating following initial use. The bits all have good heft and feel. The storage case is sturdy metal with snug cutouts for the bits and center punch. If you're looking for panel hole bits, look no further.These bits are tiny but they cut through metal duct work like butter. Just wish they offered larger diameter in this set. Comes with a carry pouch too.Not made for metalI suppose it was cheap so what should i expect, but it didn't last more than a couple weekends drilling holes in 16 guage steel. Pretty much garbageI'm not an expert on these, and haven't had this one for long or used it extensively, but it did what I bought it to do. When using it "by the numbers" (ie, to make the exact size holes you want using the diameter markings on the bit without oversizing), you might want to stop & start measuring before you actually fully progress the bit to the indicated depth. The bit arrived on time in new condition.Not good for one hole in a 304 stainless exhaust pipes. Wasn't much left after I finally finished a 3/4 in hole with help from a dremel. Should be good for softer metals or anything softer than steel really.This bit took a while to do one and it should be faster and cleaner. I've seen the expensive ones work and work well. If you need to do a few up to several this is your bit. More than that, I recommend a better option.Does not drill a starter hole for a sprayer for a stainless steel sink. This may be good for softer materials but I figured the sink is not too thick, think again no dice. I had to step through different bits just to get the smallest part of this bit in, after what seemed like forever and a smoking drill I managed to fit the sprayer through the hole.I was installing new cabinet brackets and had to widen the holes on the metal faceplate that connected to the cabinet. My standard drill bits had trouble getting a good enough grip on the plate to drill a hole. These bits went through right away. They seem pretty strong and durable.This worked really great on mild steel bar, Except the 1." For some reason, the one inch wouldn't cut, but all others did.Vendor replaced it and am now back in business.Tried using it on a steel trailer jockey needed to expand the hole from quarter of an inch to a 1-in diameter total they drill bit started off well using WD40 and going slow about halfway to where I needed to be and the bit wore out being that there's only two cutting faces and no real cutting action on the bottom of each step not that great for metalI used a couple of the bits and they were sharp enough to get the job done using an angle impact driver where it was difficult to have any pressure behind the bit. I'm satisfied, they made the job much easier then a complete disassembling of the parts to get at the location.3-bit set in metric, with punch.Perfect for my use of drilling large holes in ABS plastic boxes. Easy to use, nice smooth holes, works exactly as I need it to.