WiFi LoRa 32 V4 is a fully upgraded version of the classic LoRa development board. Since its initial in 2017, this product series has been highly favored by developers and makers
2MB PSRAM and 16MB external Flash, more suitable for UI and complex system
It is suitable for various IoT applications such as smart cities, agricultural monitoring, smart homes, industrial control,security systems, and wireless meter reading, providing developers with a more efficient and flexible development experience
USB Type-C interface with integrated voltage - regulation, ESD protection, short-circuit protection, and isolation design
High-power version with LoRa transmission power increased to 27±1dBm,Added SH1.25-2P solar panel interface.

Please your board enters Bootloader mode before flashing. Here's how:
Connect the USB-C cable, then hold down the PRG button, press the button once, and release the PRG button. After that, flash the firmware. Once the flashing is complete, remember to restart the device.
Hardware version 4.3 requires new firmware.
If you are using Heltec's development framework, please update the board package and LoRa library to the latest via GitHub.
Meshtastic, please use firmware version 2.7.20 or Please note: "Meshtastic UI" is for use with the touchscreen. For ordinary OLED screens, please do not select it.
MeshCore, please use firmware version 1.15.0 or
Specifications
MCU:-S3R2 (Xtensa®32-bit lx7 dual core processor)
LoRa Chip:SX1262
Frequency:High-power version: 863-928MHz
Max. TX Power:High-power version: 28 ±1 dBm
Low-power version: 21 ±1 dBm
Max. Receiving sensitivity:-137dBm@SF12 =125KHz
Wi-Fi:802.11 b/g, up to 150Mbps
Bluetooth:Bluetooth (LE), Bluetooth 5, Bluetooth Mesh
Battery applicable:3.3-4.4V lithium