Discount wholesale Dual Cards Cell Phones

Dual SIM cards operation allows the use of two services without the need to carry two phones at the same time. For example, the same handset can be used for business and private use with separate numbers and bills; or for travel, with an additional SIM card for the country visited.
A dual SIM cards cell phone is one which has two Subscriber Identity Modules (SIMs). Dual SIM cards adapters are available to allow cellphones to contain two SIMs, and to switch from one to the other as required. Some mobile phones are designed to work with two SIM cards, both of which may be active at the same time.
Several types of adapters are available. All of them allow one SIM to be active, and to receive calls, at any given time; they provide various ways of switching from one SIM to the other sim card. Earlier versions required the cellphone to be switched off and on again to change from one to another. Later models allow the user to switch SIM cards via a menu or by keying in a numeric code, without switching the phone off.
Normal GSM phones contain a single transceiver; dual cards phones must have dual transceivers, and need to display signal strength for both networks. A phone with a single transceiver cannot be converted to simultaneous dual-SIM operation; at most it can be made switchable with the use of an adapter.
Cell phones with simultaneous dual SIM cards capability built-in have the advantage that there are no possible legal issues, breach of contract, or voiding of warranty. They allow both SIM cards to be active simultaneously and allow calls to be received on either number, unlike adapters that make one or other number active as required.
Although battery life (talk time and standby time) of dual SIM cards phones is reduced, typically by about a third, when both SIMs are active, to compensate this they often came with better capacity batteries compared to single-SIM phones.
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