1, ESP8266 ESP-01S serial WiFi wireless transceiver module used 4MB Flash, not 1MB flash. | 2, USB Programmer selectable working mode: On-board toggle switch. UART side for serial TTL debugging by AT commands, PROG for firmware programming. | 3, Programmer USB to serial TTL chip: CH340G, please check if your computer has installed the driver before use it. | 4, ESP-01 serial wifi module can be directly plugged into the yellow pin header of the USB programmer module without any connection wires. | 5, What you will get: 1pc ESP-01S 4MB wifi module + 1pc USB programmer ESP-01S adapter module. If you have any question, please feel free to contact us by clicking "WISHIOT" under the shopping cart(you can find Sold by WISHIOT under Buy Now button) and then clicking "Ask a question".

1, The ESP-01S WiFi module is based on ESP8266 chip, so ESP-01S has all the functions and performance of ESP8266 | 2, Compared with ESP-01, ESP-01S has stronger antenna signal, and its pcb layout changed for an improvement in WiFi radio performance | 3, Flash memory upgraded from 512KB to 4MB, flash chip XMC 0H32BHIG, XM25QH32CJIG or XM25QH32CHIGU10Q shipped by random | 4, The ESP-01S is with 2X4 Pin header, and you can plug it to the interface of Burner to download the firmware to ESP-01S/ESP01S. It isalso compatible with Ar-duino IDE, please choose "Generic ESP8285 Module" board in IDE | 5, What you will get is 5pcs ESP-01S Wifi Serial Transceiver Module 4MB(pls note it supports 3.3V only). If you have any question, pls feel free to contact us by clicking "WISHIOT" under the shopping cart and clicking " Ask a question"