Quantity   Component name
1 × Tiny BLE (Bluetooth BLE + IMU sensor + LiPo battery charger) https://www.seeedstudio.com/Seeed-Tiny-BLE-BLE-%2B-6DOF-Mbed-Platform-p-2268.html
1 × LiPo battery between 300 - 900 mAh (eg: 400mAh 3.7V) https://www.aliexpress.com/item/GoolRC-Electric-RC-Battery-Lipo-3-7V-450mAh-Lipo-Battery-for-GoolRC-T5-T5C-T5W-T5G/32807738758.html
1 × Guitar finger strength exerciser https://www.aliexpress.com/item/Adjustable-Hand-Exerciser-Fingers-Strength-Practicing-Piano-Guitar-Trainer-Gripper-Tension-YS-BUY/32909690727.html
4 × Tiny cylindrical magnets (SMCO5 1.9x3mm) https://www.digikey.com.au/products/en/sensors-transducers/magnets-multi-purpose/511
4 × SMD linear magnetic sensors (90mV/mT) https://store.ti.com/DRV5053VAQDBZRQ1.aspxhttps://store.ti.com/DRV5053VAQDBZRQ1.aspxhttps://store.ti.com/DRV5053VAQDBZRQ1.aspx
1 × Thin hookup wire between 28 - 34 AWG https://www.adafruit.com/product/1446
1 × JST SH 1.0mm 2-pin battery connector https://www.aliexpress.com/item/10pcs-lot-Mini-Micro-SH-1-0mm-2-Pin-JST-Double-Connector-Plug-Wires-Cables-100MM/32867542112.html
4 × Small SOIC to DIP PCB adapter https://www.sparkfun.com/products/13655
1 × Small On/Off power switch