Raspberry Pi Zero V1.3 Single Board
"Unbelievably the super-small and super-Raspberry Pi just got even smaller and even cheaper! Pi Zero is the heart of a Raspberry Pi on a tiny 65mm x 30mm board.
With mini-HDMI, micro-B OTG USB, and the same 40-pin GPIO it still has great connectivity.
Pi Zero Features:
BCM 2835 SOC @ 1GHz
512MB of RAM
micro-B USB for data
micro-B USB for power
Unpopulated 40-pin GPIO connector
Compatible with existing HAT addons
Dimensions: 65mm x 30mm x 5mm"