SIM 800L GPRS Adapter GSM Module $ 4.99 Product Information: Operating temperature - 20+50 Module model: SIM800L (new module with performance exceeding SIM900/M590) Working voltage: 3.7~4.2V (peak current 1A, please handle it properly) Supporting network: quadband network Module size: 2.5cmx2.3cm Packing list: Adapter plate * 1