1, shell. New machine shell joints compact, seam smooth, no burrs. Refurbished machines are generally used to imitate the original shell, the seam is not flat, there are burrs, the upper and lower parts of the cell phone shell is easy to close the tight, leaving a large gap phenomenon. Identification can be used to try to insert a small finger nail into the seams of the upper and lower covers of the phone. If you can insert it, it is a refurbished machine. The surface of the shell like a new machine as frosted, and there are small particles of the phone, but also can not buy. This machine shell paint is JS sprayed on, a long time, the paint will fall off (dust on the shell of small particles, is no vacuum environment when spraying paint caused by the operation);
2, keyboard and data line interface. Due to the charger plug, data line long-term plugging and unplugging, refurbished machine charging interface will appear difficult to eliminate the black scratches. And the keyboard refurbished machines mostly use the keyboard on the old machine or imitation keyboard. This keyboard **** nature is a softer feel, without the toughness of the new machine keyboard;
3, SIM card chip contacts and battery contacts. These two contacts JS generally can not be replaced. If it is a refurbished machine, then the SIM card chip contacts will certainly leave clear friction marks, looks shiny, which is caused by too much friction. If it is a new unused chip, then the contact surface should be frosted;
4, fixed screws. Mainly look at the screws and cutter interface part there is no obvious scratches, the inner screen below the two rubber pads have no pick marks. 5, call quality. Bring your own SIM card to try, call your friends, preferably landline, ask each other how the quality of calls, call sound is clear, there is no noise, current sound, volume size there is no sudden drop in the phenomenon;
5, call quality.