4 Layer PCBs from JLCPCB - Modular Project Base
$2 for 5PCBs - order with coupon code: JLCPCBcom
Any questions about JLCPCB or ordering, pls email support@jlcpcb.com
A modular PCB concept for building sprawling analogue or digital projects.
https://support.jlcpcb.com/article/128-5-for-4-layer-pcbs