Say "Goodbye" to the old days that we have to purchase Raspberry-Pi to run Klipper.
Now we're entering a new phase that BIGTREETECH launched Pi4B adapter, which can perfectly serve as Raspberry-Pi 4B with the combination of CM4/ BTT CB1 core board.

Equipped with the standard Pi CM4 sockets, BIGTREETECH Pi4B adapter fits all versions of CM4 board, which is ideal and cost-effective replacement for Pi 4 Model B. When worked with BTT CB1 V2.1 core board, it basically could replace Pi 3 Model B as well.

Main Features

1.Standard Pi CM4 Sockets:Fits all versions of CM 4 board to replace Pi 4 model B.
2.40-Pin GPI0:Offer you with wide range of connectivity to meet users' DIY needs.
3. USB TYPE-C Power Supply Port:Make it easy to write system,and provide with stable power supply.
4. Multiple Interfaces:Comes in onboard 1000M ethernet port, dual micro-HDMI ports, CSI camera port, 4x USB 2.0 ports, etc.
5.Cost-effective to Run Klipper:The combination of Pi4B adapter and CM4/ CB1 costs you with less, and can be combined with BTT motherboards, which enables you to run Klipper
6.Wide Application: The combo set of Pi4B and CM4 can be applied in various fields, such as, writing programmes, artificial intelligence, smart home, etc.

It basically puts a CM4 into the footprint of a Pi4B adapter, along with the HDMI ports, USB-C power input, and 4x USB 2.0 ports, along with Gigabit Ethernet.
It doesn't seem the PCIe bus is exposed in any way, but it has a CSI connector on top, and a flat DSI connector on bottom. Beaware that it only supports CSI and DSI when work with CM4 board; it only supports SPI/HDMI screen when work with BTT CB1 core board.The PI4B adapter is a cost-effective replacement for Klipper system.

There are also STL files for a case on BIGTREETECH Github.

Any problems regarding BIGTREETECH Pi4B adapter,please feel free to contact us.