The Lenovo 4XC1D51447 ThinkPad Quectel CAT12 PCIe WWAN Module (SDX24 EM120RGL) is a 4G LTE Category 12 wireless communication module designed for ThinkPad laptops. It provides highspeed mobile broadband connectivity via the PCIe M. 2 interface, supporting download speeds up to 600 Mbps and upload speeds up to 150 Mbps.