This is a placeholder topic for “Stackable 0.100″ Female Header: 2x20-pin, Straight” comments.
This stackable 40-pin female header features two rows of 20 pins spaced with a 0.1″ (2.54 mm) pitch. The extended pins allow multiple units to be stacked as popularized on Arduino shields. The 2×20 size is notably used on the Raspberry Pi Models A+ and B+.Read more
So if I’m using one of these headers on a pcb that we have just had made, where do you get the “bit” for the top of the board, short of stripping the pins from a male breakaway header.
Not sure what bit you are referring to, but here is an example of how the headers are used:
To add to Jeff’s response there are 3 basic types of header, male
female (notice the short male section on top, these are perfect for soldering to a PCB)
and stacking (with longer male pins on the other side, these could be theoretically stacked forever with a PCB still mounted against the female side)
A quick couple of notes: the male header pins can be easily cut with a pair of side-cutters or snapping them(it might not be perfect though!) whereas the female and stacking headers you have to lose one in the process, usually cutting along where one pin sits.
Header pins come in different sizes, for example, a Pi uses a 2x20 header for the GPIO and a Pico uses a 1x20.
Sorry for the very long-winded reply - hopefully this can clear anything up for future makers as well!