VGBUY 3/16 x 3-3/4 Inch 40Pcs Flat Head Concrete Screws, Screws Anchor with Drill Bit,for Masonry, Block, Brick, Cement, Stacoo, No Pre Drilling, Diamond Point

I used approximately three containers (~150) of the 3/16" x 3-3/4" hex head screws and I was quite happy with the results. I was mounting 2x lumber (through 1-1/2" side) to poured concrete to attach 2" foam/gypsum with regular screws. The concrete was covered in a 1" drainage mat so I needed a screw long enough to go through 2-1/2" of material and still anchor solidly in the concrete. After using 150 of these I was quite impressed with their holding power and would definitely buy them again for other projects. For years I have been using only the brand name blue concrete screws. My frustration with the brand name ones is that they sometimes snap/break when I'm installing them with my impact driver. To their credit, none of these snapped. However, I did have a number of them strip out, which makes me believe they are made of a softer steel. When that happened I just discarded the stripped screw and used another. (A few times the issue was the hole and I needed to drill another one.) As mentioned by other reviewers there were a few that were bent out of the box, but considering how many you get for the price I don't consider this an issue. I can't speak to the drill bits as I used an SDS bit. I can say that these SDS bits worked well and I'd recommend them. https://www.amazon.com/gp/product/B09NGW761L Previously I only bought name brand ones, but considering the quality/value, I'm going to go with these in the future, especially when I buy smaller ones prone to breaking or getting dull.

I used these screws on some concrete forms to secure the forms in place on existing concrete. The first hole I drilled was not deep enough (by 1/8th inch) and the screw stripped out, so make sure you drill the holes deep enough in material like concrete. I covered the screws with a little calking to keep concrete overspill off them. I countersunk the screw holes with a Forstner Drill Bit to make "scretting" easy. I was not worried about the screw holes in this application, because they will be easily filled with concrete patch before resurfacing the entire project with a new antislip concrete finish. Note: When drilling into hard material like concrete, it's important to keep the bit cool or you will wear it out before you finish the first hole. A "regular" drill will just wear out the bit. You must have a drill with a "hammer" mode enabled. I use the "Skill" Model HD6294B-00. It's a versatile drill that I use for everything.

Worked as expected. Good item at a good price, shipped quickly. What more do you need?

Quantity good for the price, but the head stripped easily

Great quality

Worked out great

Good strong screws. Used them to mount a heavy mirror onto a concrete block wall. They did exactly what I expected then to do. Good product!

The screwdriver slots are painted over with a thick coating to the extent that the entire slot is filled with paint and thus is useless. The included drill bit won't drill thru my poured concrete basement walls even tho I'm using a heavy duty hammer drill that works with other brands of bits. Don't waste your money and jeapordize your safety on a bad drill bit snapping.

All my walls are concrete and these screws have been fine. I have used wall plugs with all of them and I’m trusting them with some fairly heavy and/or sentimental items. They’ve not skipped a beat so far (about 18 months).