Service：I can not talk about product quality, nothing works! I bought these on the recommendation of the sales person. I asked several times for wiring instructions for 2 months. Then he said I needed STM32F407 $40 each to make the HC SR104 work. I said it was too expensive. I bought 4 and then found them on Amizon for $10. I'm still waiting for wiring instructions. Also bought a small car. No asseemply instructions, no wiring instruction. I can not afford to work with your company any more. I have been working with your salesmen since July 2024 and I still do noit have what I need. 

Delivery： 10/10 Quality： 10/10 Service： 10/10 Excellent Supplier with High-Quality Products