This expansion breakout board duplicates every pin of a compatible ESP32 development board (1-to-2), creating two accessible pin rows so you can reuse all GPIOs without modifying the original board. It is designed for reliable connections, fast prototyping, and neat wiring in smart home and embedded projects. Key benefits Reuse all pins: Duplicates each ESP32 pin into two outputs so multiple peripherals can be connected without swapping header wires. Ready to use: Fully soldered, double-layer PCB is supplied assembled — no additional soldering or assembly required. Stable signal and contact: Double-layer PCB traces and mirrored pin connections reduce poor contact and unstable signal issues common with single-sided breakout methods. Easy development: Built-in support for Lua and standard ESP32 Wi‑Fi modes (AP, STA, AP + STA) simplifies firmware and network setup. Main features Function: Breakout/expansion board that splits each ESP32 pin into two accessible pins for easier wiring and parallel connections. Compatibility: Designed specifically for 38-pin narrow-type ESP32 development boards using the ESP-WROOM-32 module. Compatible only with the 38-pin narrow-hole, no installation-hole version of the ESP32 development board — not compatible with other versions. Construction: Double-layer PCB with pin connections on both sides for improved reliability. Ready condition: Fully soldered and preassembled so you can plug in and start wiring immediately. Performance and practical details Maintains original board accessibility while adding duplicated pin access for sensors, relays, displays, and other modules. Improves contact reliability versus single-sided or hand-wired solutions. Supports the ESP32’s network modes (AP, STA, AP+STA) and Lua programming for quick development cycles. Typical applications Smart home hubs: Connect multiple sensors, relays, and actuators to a single ESP32 while keeping the development board accessible for debugging. Prototyping and testing: Use duplicated pins to attach test equipment, breadboards, and temporary modules without removing existing connections. Multi-module projects: Drive displays, I/O expanders, and communication peripherals in parallel while keeping neat, reliable wiring. Compatibility reminder Use only with the 38-pin narrow-type ESP32 ESP-WROOM-32 development board that has narrow header holes and no installation holes. This expansion board is not compatible with other ESP32 development board variants. What you get A fully assembled, double-layer ESP32 expansion breakout board that duplicates pins (1-to-2) for the specified 38-pin narrow ESP32 ESP-WROOM-32 development boards, ready for immediate use.