The ExtensionBlock is an add-on board for the Raspberry Pi and compatible System-on-Chip platforms. It is a three-way distributor for the 2×20 GPIO pin header. You stack it on top of the existing 2×20 pin GPIO header. It allows you to stack two full-size HATs side-by-side onto the Raspberry Pi. In addition to the pin headers for the HATs, the ExtensionBlock has a third 2×20 pin out so that you even have access to the GPIO pins when two HATs are installed. This should give you a maximum of comfort during development and debugging of your project. Features * Three-way distributor for 2×20 GPIO pin header * First and second 2×20 pin out faced towards the original direction, while the third 2×20 pin out is faced in opposite direction. * Allows side-by-side installation of two full-size HATs * Comes with two stackable 2×20 pins headers. You need to solder these to the board. * Compatible with Raspberry Pi and comparable systems https://elecena.pl/product/22718420/extensionblock-discontinued 2023-03-07 https://elecena.pl/product/22718420/extensionblock-discontinued 2023-09-14 https://elecena.pl/product/22718420/extensionblock-discontinued 2023-12-27 https://elecena.pl/product/22718420/extensionblock-discontinued 2024-09-19 https://elecena.pl/product/22718420/extensionblock-discontinued 2024-11-29 https://elecena.pl/product/22718420/extensionblock-discontinued 2024-11-30 https://elecena.pl/product/22718420/extensionblock-discontinued 2025-05-13 https://elecena.pl/product/22718420/extensionblock-discontinued 2025-11-28 https://elecena.pl/product/22718420/extensionblock-discontinued 2025-11-29 https://elecena.pl/product/22718420/extensionblock-discontinued 2026-03-11