This 2x20 header can be soldered onto a circuit board so you can easily connect a 40-pin ribbon cable directly from the Raspberry Pi. This header is also great for soldering onto a Raspberry Pi Zero so you can then put pHATs and other addon boards onto it
Connect your own Raspberry Pi addon board with this 2x20 female header. The female header part is 8.5mm tall which is good for small HATs that don't cover the USB and Ethernet ports.
This is the smallest Raspberry Pi SBC available at the moment. The board is just half the size of a Raspberry Pi Model A+, and has Bluetooth and WiFi onboard!