丰满少妇被猛烈进入无码,国产精品亚洲欧美在线播放操,无遮挡又黄又刺激又爽的视频,久久久久亚洲AV成人

in fact,Plastic shellIt has already penetrated into people's life and work, and has brought us a lot of convenience. The plastic shell has a certain protective effect on electronic products. Mobile phone plastic shell is very common in life, which can not only prevent falling, but also have a certain insulating effect. The GPS shell can effectively protect the GPS circuit board and prolong the service life of the GPS locator; The electromechanical waterproof shell can play a good role in waterproof protection for outdoor meters.

Plastic shell is widely used in various electronic products. According to its purpose, it can be divided into GPS locator shell, electromechanical shell, mobile power supply shell, mobile phone shell, etc. Although many mainstream high-end products are increasingly made of metal, it can be seen that metal fuselage is a trend. In terms of appearance, the texture is richer, the feel is more comfortable, and it can better reflect the taste of high-end mobile phones. For example, the metal material will cause interference to the signal, paint falling off and other shortcomings. However, the advantages and disadvantages of plastic shell are gradually being effectively developed by people, and the practicality of plastic shell has been brought into full play. Plastic material is light, elastic and not easy to deform. Among them, the color matching and pattern of plastic shell can be realized through oil spray and silk screen printing process, which is simple to operate, low cost and more convenient for people to use.

For example, the commonly used ABS engineering plastics, namely ABS engineering plastics, namely pcabs (engineering plastic alloy), is named plastic alloy in Chinese in the chemical industry because this material not only has the excellent heat resistance, weather resistance, dimensional stability and impact resistance of PC resin, but also has the excellent processing fluidity of ABS resin. Therefore, when it is applied to thin-walled and complex shaped products, it can maintain its excellent performance and the formability of materials composed of plastics and esters. The most serious disadvantage of ABS engineering plastics is its heavy quality and poor thermal conductivity. Generally speaking, ABS engineering plastics are used by most manufacturers because of their low cost. At present, most plastic shells use ABS engineering plastics as raw materials.