BG5ELQ I've forgotten about my friends in Zhejiang and Shanghai, sorry! If there are U-band restrictions, then I can only use K5/6.
If you're already a fan of digital products, you could also consider buying a Xiaomi walkie-talkie 2nd generation on Xianyu. It has UV dual-segment verification codes, a Chinese interface, Bluetooth pairing, and can connect to existing Bluetooth headphones. It has a long battery life and is suitable for those who don't like tinkering but enjoy talking. However, you need some experience using Xianyu.