JOOI is there a name for these?
I found a few included with a new door lock/latch/handle set the other day
- coarse pitch for the first 3/8" and then a much finer pitch toward the head end.
Never seen ones like that before, and I'm surprised they don't just chew up the wood when driven in and result in a weaker fixing (I assume the idea is that the coarser ends make them easier to initially dig into the wood for folk who don't like drilling pilot holes?)
cheers
Jules