1-2-3 Parallel Blocks, metric 25x50x75 mm + Box

Now, if you are not a machinist or engineer you may not have come across 123 blocks before, but this is to miss out on something very useful indeed. 123 blocks refer to the dimensions 1" x 2" x 3" - so if you are an imperial hater then sadly you are stick with the nomenclature. Much more snappy than 25.4 x 50.8 x 76.2 blocks...... So, what you have is a block that is - or is supposed to be perfectly square in all dimensions to be used for setting machine tools. But, it has uses for the home user as well which makes some things much easier. In particular if you have a chop saw or mitre saw, you will know that the marks on the machine are more of a guideline not really to be used for accurate cutting. With a 123 block you can easily set up the 90deg cut in both horizontal and vertical plane easily. Likewise if you have a saw bench or a pillar drill the same thing applies. Easy way to set up your cuts. Now, as for accuracy? Pretty good I'd say. I tried cutting two bits of metal in opposite sides and then turned and matched them to see if they were the same, and they were. Near enough accurate for the home user for sure. The machined finish is very good and they come well boxed in a protective film of anti- corrosive waxoil. Overall a great value buy if you want to have an accurate setting up block.

I use these for woodworking so don’t need the accuracy for engineering. They have been checked with the digital callipers and are with acceptable tolerances for me. They are used as set up blocks for fine tuning tools and have found them to be square as well as dimensionally accurate. These are metric which is also a bonus.

Thes look nice in there little wooden box

These are as close as I can measure to parallel and the right size, within a couple of microns compared to some gauge blocks. Mine have M10 thread. They come in a wooden box that would benefit from a divider to stop them bumping together, and without bolts.

Very slightly smaller than the usual 1"x2"x3" blocks, these are 25mm x 50mm x 75mm. Spot on with a Mitutoyo digital caliper.

The size of the blocks appears to be accurate (25x50x75mm) but that’s pretty much it. The holes are substantially off centre. To the point one can see the problem with a naked eye. To be on the safe side, I did measure the position of the holes and the measurements confirmed the problem. The corners of the boxes were done very roughly with too much metal removed unevenly from the blocks. Obviously, I have to return them. Unfortunately, I have to recommend buyers who need 1-2-3 blocks to buy another brand.

Metric metic metic…. They cost a little more but they are actually metic and accurate. Although I’m using them for woodwork but seem reasonable quality worth a buy. I was sick of buying from other companies saying they were metric and when they came they weren’t

Very useful piece of kit. Well machined and a good weight to them. Feel high quality. Definitely accurate enough for me as a weekend DIYer. Came well protected in their pack, oiled, and individually wrapped.