Quantity   Component name
8 × 9g Servo motor link: https://www.banggood.com/TowerPro-SG90-Mini-Gear-Micro-Servo-9g-For-RC-Airplane-Helicopter-p-1009914.html?p=E01411629100201406T1&custlinkid=359550
1 × White LED link: https://www.banggood.com/Geekcreit-375pcs-3MM-5MM-LED-Light-Emitting-Diode-Beads-Resistance-Lights-Kits-Bulb-Lamp-p-1027601.html?p=E01411629100201406T1&custlinkid=669272
1 × Small PCD push buttons link: https://www.banggood.com/100pcs-Mini-Micro-Momentary-Tactile-Tact-Switch-Push-Button-DIP-P4-Normally-Open-p-917570.html?p=E01411629100201406T1&custlinkid=669260
1 × 12V car horn
1 × 200 ohm resistor link: https://www.banggood.com/Wholesale-Geekcreit-600pcs-30-Kinds-Value-1-14W-Metal-Film-Resistor-Assorted-Kit-20pcs-Each-Value-p-53320.html?rmmds=search&cur_warehouse=CN
1 × Arduino nano link: https://www.banggood.com/Geekcreit-ATmega328P-Nano-V3-Module-Improved-Version-With-USB-Cable-Development-Board-For-Arduino-p-933647.html?p=E01411629100201406T1&custlinkid=255135
1 × prototype board 4cmX6cm type: 107822J2H link: https://www.banggood.com/Geekcreit-40pcs-FR-4-2_54mm-Double-Side-Prototype-PCB-Printed-Circuit-Board-p-995732.html?p=E01411629100201406T1&custlinkid=669188
1 × 2S lipo battery link: https://www.banggood.com/7_4V-2S-2000mAh-8C-Lipo-Battery-Compatible-for-Frsky-ACCST-Taranis-Q-X7-Transmitter-p-1249125.html?p=E01411629100201406T1&custlinkid=669244
1 × DC to DC step down regulator link: https://www.banggood.com/LM2596-DC-DC-Verstellbar-Step-Down-Schaltregler-Power-Supply-Module-p-88252.html?p=E01411629100201406T1&custlinkid=255154
1 × 5V relay to switch the car horn on and off and other functions link: https://www.banggood.com/5V-8-Channel-Relay-Module-Board-For-Arduino-PIC-AVR-DSP-ARM-p-74110.html?p=E01411629100201406T1&custlinkid=669239
1 × Heat shrinks link: https://www.banggood.com/328pcs-Heat-Shrink-Tubing-Insulation-Electrical-Shrinkable-Tube-Sleeve-Cable-21-p-1362019.html?p=E01411629100201406T1&custlinkid=669227