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Waveshare 4 Port USB HUB Hubs HAT Compatible With USB2.0 1.1 For RPi Raspberry Pi Zero A+ B B+ 2 3 Model B Serial Debugging Onboard USB to UART: Amazon.co.uk: Computers & Accessories
LTE base hat, Raspberry Pi 4 Uart Occupy (has very simple answer) - 3G/4G<E Base HAT - Sixfab Community
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