Quantity   Component name
1 × Wemos D1 Mini I'm using the older version that has the big ESP8266 RF shield on the body. If you use the newer ones you will have to edit the 3D printed part to make it fit right.
1 × 5mm LED
1 × 220 ohm Resistor Current Limiting resistor for the LED.
1 × A bit of wire wire to connect the resistor, LED, and wemos