Hymnorq Aluminum Alloy Miniature Hand Tool Set with 1 Three-Jaw Chuck and Hex End Pin Vise and 10 Twist Drill Bits for Delicate Manual Work…

Went and grabbed the 2mm to drill some pilot holes before I used my impact to screw together some boards and the bit broke and these aren't even real metal like they look on the outside. Then I was using another bit, 8mm I believe (I should put a picture of them broken, but I dropped it on the garage floor and it broke too? How does a bit break from a 4 foot- 5 foot drop? Must be very cheaply made. This is why I will only buy name brand items that are well made, these are not, I promise you, nothing but trouble for me.I am a carpenter by trade and use drill bits all the time, these I bought fo rmyself. No good, Do not Buy!

I live in Thailand where building construction is NOT like in the USA. My residence has an iron frame covered with an odd thin composite wall board that makes any normal task, such as hanging a picture or putting up towel bars a challenge. I bought some drill bits here but they were powerless to puncture my walls. In desperation I searched Amazon and found these bits and had a friend from the USA deliver them. WOW!I breezed through all my projects. I practically keep them under lock and key to make sure they don’t wander off, as tools have a way of doing.

I figured these were just Chinesium steel when I ordered them, but they appear to be High Speed Steel, which is pretty amazing at this price. I'm not sure if they're cobalt HSS M35, but they're at least M2. I've made probably a hundred holes hand-drilling mild steel auto bodies with no dulling or chipping. I even drilled out a 304 stainless screw in my press with these and a bit of patience. If you're looking for something to drill fastener holes for angle iron, I'd say these are the ticket.The only thing I would complain about is the titanium nitride coating (added for reducing heat and friction) extends down the entire shank of the bit, which makes the shank prone to spinning in the chuck as it scrapes off the coating into burrs. Still giving 5 stars though because of the price.

At the time I purchased these, I only intended to use them for light duty (drilling into polymer). However, as fate would have it, I had to use them to drill into hardened steel, and much to my surprise, they performed admirably. It was a pleasant surprise (I was expecting "Chinese junk") and I'm very happy with this purchase; especially considering that it's a METRIC set, which is difficult to find (in the USA). I wish the set had a 1mm bit, but oh well. It's just a preference, not anything against the quality of the bits in this set.=============Update 1/16/18=============My rating has changed from 5 stars down to 3. I needed to drill into metal again--actually I wasn't even drilling new holes, but just "chasing" already existing holes to expand them--and neither the 4.5mm or 4.8mm bits would do anything. They just spun around getting hot, without cutting anything. I even tried the 5mm bit, even though that was too big for my purposes, and it also did nothing but spin. Thus, I've used four of the bits (4, 4.5, 4.8, and 5mm), and only one of them did anything. The one that actually worked did its job well; the others are a HUGE disappointment.=============Update 1/25/18=============Kudos to Migiwata customer service (thank you, Bella!). After hearing about my not-so-pleasant experience with these bits, they sent me a second set. Apparently their original supplier had run dry, and they had to use a second, temporary supplier while the original caught up with demand. The first set that I received was from the temporary supplier. The new set is from the original supplier, and the bits seem to be in order in this new set. So how do you tell the difference? By the case (see photos). The set with the blue dot on the case--which is a plastic retainer to keep the case closed--is from the original supplier. Now if you happen to get a set without the blue dot, don't panic. Just because I got a subpar set that slipped through the manufacturer's quality control process doesn't mean that you did, too. Try the bits out first. WORST case is that Migiwata customer service takes care of you like they did me; best case is you don't even have a problem. As for me and my review of this product, I'm a happy camper again and am bumping my rating back up to 5 stars. The bits are great (make sure to use a good cutting lubricant/coolant) and Migiwata customer service is stellar.

Excellent. Been metalworking for 40 years through high school and a university then 'Captain Modify' from there, on motorcycles, building telescopes, scope mounts, and tons of fabrication jobs around the house, generator, solar you name it. Always had trouble with drill bits (even bought a Drill Doctor). I have some Temo cobalt/HSS step bits that really eat metal, but I can't use them on everything. I often buy the Ryobi sets at Home Depot, but stainless is going to be a problem. These seemed to have good reviews and I can confirm these are really good. I just drilled (4) 5 mm holes through 3/8" mild steel. Beautiful. Swarf spirals all the way through. I'm impressed. I would buy these again.

These bits work very well. They did exactly what I needed them to do for a bad situation of bolt extraction. I wasn't expecting them to hold up as well as they did, mainly because of the price.Just make sure you buy cutting oil and use it constantly while using these in order for a better outcome and to extend the life of the bits. If you don't apply cutting oil, the bill will probably get too hot and break quickly. But that is the case for all drill bits of this type.

This is the best drill bit for drilling out stainless steel screw which is very hard metal. Do not buy the titanium coated for hard steel they go blunt in second.

Just what i was looking for to drill into stainless steel..!

this product doesn't seem to be true cobalt bits like I've purchased in the past. I used the 5.5 to attempt to drill through some thin stainless steel, but it wouldn't able to do this (despite using a drill press, low speed, drill oil etc.etc.) I didn't want to try the other bits as the quality is not what it seems. Disappointed as I waited a long time to get these bits. I will be returning these as they are not as advertised. Spend the $ and get some better bits.

Ok quality bits, I wish there was more carbide bits that were easily available, these bits are useless for hardened steel/ security grade steel. I need way better than this. Even 8% cobalt is not good enough. A carbide masonry bit does me better.

I originally gave these bits a poor review, however I found out I was trying to drill into hardened tool steel and this was the cause of failure. Once I did some spot annealing on the metal, i was table to drill through it easily on losw seed with tapping oil.