Amtech F2800 3 Piece 400mm Masonry Drill bit Set

Not sure about their use for other than d.i.y. purposes but for what I needed them they are ideal.Used both the 8mm and 9mm to drill through a cavity external house wall. Double brick. They went through both without much effort and there doesn't look to be any deterioration of the tips. No doubt the 10mm drill will be the same.I did have to start with a short masonary bit of the same size because these drill are not straight which was apparent by turning the drill on before attempting to start the holes.To help prevent any "break out" I measured the wall thickness and wrapped a bit of red insulating tape around the drill at just less than the wall thickness and reduced the force for the last 10mm.So, for the price, for me, they did exactly what I required.

Decent cheap drill bits. Drilled 3 holes the full length through brick with a cordless hammer drill and they did the job. They suffered somewhat when some of the bricks were damp inside, clogging the flutes. But I expect this would happen on even the best bits. Biggest complaint was the bits had a bit of a bend in them making them wobble a bit in the drill.

Avoid, yet again used all 3 to drill a hole, very disappointed, I'm not bob the builder but these are crap, bucked at the cavity, then bent at the brick, my little black and decker (cordless) couldn't use it so got the big boy out and that struggled I guess you pay for what you get, just don't expect to cut through butter

Needed to get through the cavity my local DIY was charging a fortune for single 400mm drills so thought these would be worth a try since they were about a third of the price of one drill bought locally.I went through as far as I could with a normal length drill and since I only have a 500W drill went through with the 8, 10 and finally the required12 mm. The result the required four 12mm holes with no problem and the drills are still sharp. How long they would last in daily use I don't know, but if you are a DIYer who only requires a few holes, then these drills are more than up to the task and at an amazing low price, buy them.

Like other Am-Tech stuff that I've bought, the product is cheap and does the job. These drills are plenty long enough to go through a cavity wall and all will fit a standard 13mm chuck.The only issue - and it might be because the packaging was more in keeping with a poster - there is a slight bend in each drill bit. It's bearable and I used the larger drill easily enough, but because the drill was slightly curved there was a bit of vibration.Overall though, given the price I can't complain.

These drill bits are truly awful and I have requested a return on them. The 8mm but doesn't even have a masonry tip and the tip on the 12mm looks like it was welded on in the dark, by a blind man. Yes they are cheap, but I was expecting better quality than this. Very disappointed.

Awful quality, I bought these bits to fit an external power socket. I need to drill through one solid breezeblock and one modern red brick. Using all three, I have been unable to accomplish this seemingly simple task. The two narrower bits were bent, all three seemingly blunt within seconds. Avoid.

Did the job i needed them for so in that sense they were good, however, they did seem to flex a little under pressure. At the end of the day you get what you pay for, i only needed them for inside work which they did great. Can not say what they would be like on the outside )we have accrington brick) as i havent tried them yet. WIll update when i do. Other than that they are ok and will do great for small jobs.