Basic Parametersource from : https://feasycom.com/product-Ultra-Small-Size-BLE-5-1-Module.htmlModule No.FSC-BT690Bluetooth StandardBLE 5.1Transmit Power-19.5 dBm to +2.5 dBmFrequency2.400 - 2.483.5 GHzProfilesGATT Central & Peripheral, customizableDimension5.0mm X 5.4mm X 1.2mmPower Supply1.1V~3.6VInterfaceUART, I2C, SPI etc.AntennaExternal antenna required.HighlightsBluetooth 5.1 Specifications, Ultra-small Size, Affordable CostFeatures:*2.4-GHz RF Transceiver Compatible with Bluetooth Low Energy (BLE) 5.1*Ultra-small Size 5.0mm X 5.4mm X 1.2mm*Supports Multiple BLE Connections (Up to 3 Connections)*Programmable Transmit Output Power from -19.5dBm to +2.5 dBm*Operating Voltage: 1.1V to 3.6V*Supports SPI, UART, I2C InterfacesApplications:*Industry Control*Home Automation*Healthcare Applications*Bluetooth Beacons*Other IoT Applications