Size: Dipole Antenna included MKR GSM 1400 has been designed to offer a practical and cost effective solution for makers seeking to add global GSM connectivity to their projects with minimal previous experience in networking. It is based on the ATSAMD21 and a SARA-U201 GSM module. It provides global 3G / 2G connectivity, analog and digital pins. The design includes the ability to power the board using a LiPo battery or external power source rated 5V. Switching from one source to the other is done automatically. ATSAMD21 ARM Cortex-M0+ 32-bit Processor 32kb SRAM with 256kb Flash Memory Micro SIM Card Port SIM Card Not Included Powered by a LiPo Battery ( 3.7 v) or External Power Source Rated 5V USB Port for Data and Power