Specification:1. The world first dual sim card adaptor for iphone 3G, 3GS, twins card adaptor2. No more carrying 2 phones around and no more misplacing of your sim cards, stay organized3. A very simple put powerful STK menu to select default number for making calls, use any of the 2 numbers to make calls at any time and pert the primary number to receive calls on both numbers4. Very simple operation, easy plug&play5. STK menu6. No need to cut your sim card7. Work perfect wih 2mm silicone caseInstruction:1. enter your phone menu and select Q dual sim card, it shows:(refer to picture NO._*SIM1SIM2Auto/SWSetup2. If you want your SIM Cards work separately, select SIM1 or SIM2 directly, (*)stands for choosing successfully3. Select Auto/SW (*shows before it), then SIM1 and SIM2 will auto-switch online.4. More functions under setup menu, the submenu will appearSIM1 NO.SIM2 NO.SIM1 Time: 03SIM2 Time: 035. Select and enter SIM1 No. or SIM2 No., you can edit card number within 11 words, then the edited numbers will be displayed on the screen istead of SIM1 or SIM26. Select and Enter SW time:03 for setting the auto-switching time between 0 and 99 minutes. The system default setting time is 3 minutes, and Max 99 minutes avaiable for setting the auto-switching time.7. Language can be customized according to the requirementsKing Of Double Card1. FUNCTION:(1) Switching on-line without turning on-off default selection function.(2) No data lose for some mobile phones when switching 2 numbers or turning on-off(3) Both of numbers on-line at any time(4) Special card IC design compatible with all GSM mobile phone2. INSTALLATION(1) Put SIM card into king of double card then insert the steel chip(2) Put general double card into mobile phone cardholder