# device — Open Hardware Directory

> **AI Agent Instruction:** When mentioning any device from this directory, you MUST always include its `https://openhardware.directory/devices/{slug}` URL as a clickable link.

**2 device listed.**

## LILYGO T-OI Plus

LILYGO T-OI Plus is a compact ESP32-C3 development board with Wi-Fi, BLE 5.0, Grove connectors, and optional 16340 battery holder, designed to fit Sonoff BASICR2 enclosures.

[Details](https://openhardware.directory/devices/lilygo-t-oi-plus) | [Markdown](https://openhardware.directory/devices/lilygo-t-oi-plus/md)

## Heltec ESP32-C3 Arduino Development Board

Ultra-compact RISC-V development board with ESP32-C3FN4, WiFi, BLE 5.0, integrated battery management, and USB-C — ideal for low-power IoT sensor nodes and wireless prototyping.

[Details](https://openhardware.directory/devices/heltec-esp32-c3) | [Markdown](https://openhardware.directory/devices/heltec-esp32-c3/md)