Datasheet

This board makes it easy to see if you're connecting your wires
correctly to the Raspberry Pi GPIO. Design licensed from Low Voltage
Labs’ Pi GPIO Reference Board, with some changes - including
grouping the pins into categories like I2C, IO, UART, SPI, and power.
It's only 0.8mm thick and makes a great keychain for the Pi enthusiast.
Simply slide it onto the 2x20 GPIO header, then you can plug in
premium jumper wires with female sockets on top.
This version works with the Raspberry Pi Model B+ / Pi 2 / Pi 3. It does
not work with the Raspberry Pi Model B.
 Dimensions: 66mm x 23mm x 0.8mm / 2.6" x 0.9" x 0.03"
 Weight: 2.4g