🔧 Tandy Leather Craftool® Pro Line Diamond Stitching Chisel - 6 Prong (1/8" (3mm) Spacing): A Professional's Must-Have for Precise Leather Stitching Review

I have been using this product for several years and am very happy with its performance. It's not 3mm though, it's closer to 6mm and I'm not sure where they got the 3mm from.

These chisels work as expected and are a great help when sewing leather. I recommend them even if you will be doing a small amount of sewing.

I couldn't finish my project with these because they were very faded. As others have said, for the price it works if you're just trying it out and don't want to spend more on the right tools. You can start here and upgrade when you're ready. I was uncomfortable working with them. but it's hard to complain when it's less than $20. The low price is the only reason I gave it three stars. It doesn't cost more than its price.