Quantity   Component name
1 × ESP32 microcontrollers with integrated Wi-Fi by Espressif Systems
1 × RM3100 Precision 3-axis magnetometer board from PNI
1 × RTC DS3231 High precision real time clock board
1 × Micro-SD Breakboard Stores magnetometer data and WiFi settings
1 × 18650 Battery Shield Board V3 Micro USB Charger project power supply
1 × 'Helmholtz coil' 10 turns of AWG 35 wire, R 8.6cm Self made