This type of chisel is not suitable for penetrating through the thick leather.
If the leather is thick or hard, use chisels to go halfway through, then, use an awl to complete the holes.
High-quality blades finished one by one by hand.
Creates stitching holes in diagonal patterns.
Heat treatment and anti-rust treatment are done.
This blade has constant width and thickness so the thickness of the leather doesn't have an effect on the size of the hole.