M66 Quad-band GSM/GPRS Breakout 3.4V-4.4V

The M66 breakout board integrates the quad-band GSM/GPRS engine (based on the Quectel M66 module) into a ready-to-use development board aimed at makers, IoT developers and system integrators. It supports GSM frequency bands at 850/900/1800/1900 MHz, enabling worldwide 2G connectivity (voice, SMS, GPRS data) and is powered via 3.4 V to 4.4 V DC (ideal for single-cell Li-ion supply or regulated 3.7/4 V). The board typically provides SIM card slot, antenna connector (or built-in antenna), UART interface for AT commands, and additional breakout pins for audio, power control, status-LED etc. The form factor makes it suitable for embedding in remote, battery-powered or mobile applications where low cost, global cellular connectivity and modest data rates suffice. In short, it offers an off-the-shelf gateway for voice/SMS/GPRS in projects like asset trackers, remote sensors, industrial controllers and similar. On the hardware side the design emphasises ease of use: level-shifting/logic-level matching likely pre-built, on-board power regulation/filters (depending on variant), and break-out for peripheral connections. The underlying M66 module itself offers multi-slot GPRS (Class 12) and a robust low-power footprint which suits embedded use.