I have always used a Three date SIM card with the unit (as I have a phone contract with them also). I've added using Three as I've never tried another data SIM card with it.
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TIANJIE 4G MIFI LTE WiFi Router Portable Wi-Fi 6 3000mAh Pocket Mobile Network SIM Router WiFi Hotspot For Business Gaming
Aliexpress UK
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Plery 4G/5G Mobile WIFI Router 1200Mbps 4G LTE Wireless Router Portable Pocket MiFi Modem Mobile WiFi Hotspot With Sim Card Slot
Aliexpress UK
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Unlocked HUAWEI E5573s-856 e5573 Dongle Wifi Router 4G Mobile WiFi Router
Aliexpress UK
The Three 4G MiFi Modem, model TCL MW63V3, is a portable mobile Wi-Fi hotspot in black. It is unlocked and features dual-band technology, providing reliable and fast internet connectivity on the go. This modem is perfect for those in need of a mobile broadband device for home networking and connectivity purposes. With the Three brand known for its reliable network coverage, this modem ensures a seamless and secure internet experience.
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XUNYOU-LINK 4G SIM WiFi Router 300Mbps High Speed WiFi6 Wireless WiFi Modem Support 32 Device Four Antennas Enhanced WIFI Router
Aliexpress UK
4G LTE portable Wi-Fi hotspot. Original Huawei battery. Original Three UK back cover. Originally for Three UK, may be locked to that network. Works on 4G/LTE bands used by most UK providers (O2, EE, Vodafone, etc.).
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XUNYOU-LINK 4G SIM WiFi Router High Speed WiFi6 Wireless WiFi Modem 300Mbps Support 32 Device Four Antennas Enhanced WIFI Router
Aliexpress UK
As per the pictures, been used but works well Thanks for looking :-)
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Smart Wifi remote mobile phone two-way video dialogue elderly children monitoring home mobile phone high-definition remote camer
Aliexpress UK
It has a few black marks on it. Blazing-Fast 5G Speeds: Experience lightning-fast internet speeds with 5G technology, enabling you to download, stream, and browse without any lag or interruptions. Enhanced Security Features: Protect your network and personal information with advanced security protocols and features to keep your data safe from cyber threats.
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INQMEGA Solar Camera 4G SIM/WIFI 6K 12MP 15X ZOOM three Lens Recording Dual Screen Human Auto Tracking Color Night Vision UBox
Aliexpress UK
The Huawei E5573Bs-332 Three Mobile Wi-Fi is a reliable and convenient device for travellers on holiday. With its 4G WiFi capabilities, this mobile Wi-Fi allows users to stay connected wherever they go. The Huawei brand ensures quality and performance, making it a trusted choice for those in need of a portable internet connection while on the move. With its model number E5573Bs, this device is a practical and efficient option for staying connected during trips and adventures.
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SHIWOJIA 6K 12MP 15X ZOOM Solar Camera 4G SIM /WIFI three Lens Recording Dual Screen Human Auto Tracking Color Night Vision UBox
Aliexpress UK