Detailed tutorial with hardware information about this shield: 

https://learn.sparkfun.com/tutorials/retired---mg2639-cellular-shield-hookup-guide/all#hardware-overview



Link to datasheet:  https://www.digikey.in/en/htmldatasheets/production/1824282/0/0/1/mg2639-v3-datasheet

Included is ONE unused in bag Sparkfun MG2639 cellular shield  board as pictured.


Note:  I am unable to provide any sort of SUPPORT for these devices.   They're brand new, and I've used a few of them myself so I know they're working - but by buying these from me you accept that I cannot and will not provide guidance on HOW to use them or troubleshoot any particular functionality. They come with no warranty and are priced accordingly.