Raspberry Pi A+, B+, 2 , 3 and 4

Our Raspberry Pi Plus range of expansion boards are designed using the HAT mechanical specification to ensure maximum compatibility with third party Raspberry Pi HAT boards which can be stacked above our expansion boards using the optional four post mounting kits.

All of our Raspberry Pi Plus expansion boards and adapter kits are compatible with the Raspberry Pi A+,  B+, Raspberry Pi 2 Model B, Raspberry Pi 3 Model B, Raspberry Pi 4 Model B and Pi Zero and can be stacked to mix and match your requirements so you could add analogue inputs, up to 128 extra input / output ports, serial RS232 communications or a real time clock module.

Raspberry Pi 3

Raspberry Pi HAT vs AB Electronics UK expansion boards comparison:

  Raspberry Pi HAT Our Expansion Boards
Full size 40 pin GPIO connector Yes Yes
Follows the HAT mechanical specification Yes Yes
GPIO connector with 10-12mm spacing Yes Yes
Limited to one HAT on your Raspberry Pi Yes No
Multiple stackable expansion boards on your Raspberry Pi No Yes


The Raspberry B+ model was released on the 14th August 2014 and has a redesigned PCB compared to the older model A and B. The new B+ has an extra two USB ports and the 26 pin GPIO port has been replaced with a new 40 pin GPIO port which has extra I/O pins and support for a rom chip on non-stackable expansion boards called  ‘HATs’ (Hardware Attached on Top).

In November 2014 the Raspberry Pi A+ was released as a low power alternative to the B+.  The A+ does not include ethernet, only has one USB port and is smaller than the B+.

In Febuary 2015 the Raspberry Pi 2 Model B was released to replace the previous model B+, the new Raspberry Pi 2 Model B has  a faster 900MHz quad-core ARM Cortex-A7 CPU and 1 GB Ram.