Oddly the 2.4mm chisel is probably the most common chisel as it is not included in any of the bulk packs and therefore had to be purchased separately. But that's okay, that's the way it is. It works well and so far have had no issues with heat, no chipping, canning and preserving the jar. This isn't Hakko; it's not worth it either. I solder every once in a while, not every day, so this is perfect for me.