The Car use phone holder is designed for driving safety and has become the trend pursued by many car owners. However, There are good and bad intermingled in the market of car use phone holder, how to choose an excellent and reliable Car use phone holder is a very serious topic. The essence of this problem is ultimately the customer's understanding and trust in a product. Due to the unreasonable design of some old holders on the market, it will block the air vent, which affects the normal operation of the air conditioning system. Secondly, some products have defects in appearance and practicality, which cause the supports to be too large, which will affect the owner's line of sight and endanger safe driving. In addition, the stable performance and the anti-shake performance is poor, and the safety of the mobile phone is greatly challenged. Furthermore, the quality of the product is, in a certain sense, an important indicator to tell whether a product meets the standard or not.