GCT2406 is a small-size  wireless module for BLE4.2 or BLE5.0 independently developed based on TI CC2640, with built-in ARM dual core processor. This is internally integrated with 128KB programmable flash memory and 8KB SRAM. Due to its unique ultra-low power sensor controller, it's very suitable for connecting external sensors, and also suitable for autonomously collecting analog and digital data when the rest of the system is in sleeping mode.