Shenzhen Allah Information Technology Co., Ltd. , (our factory :Shenzhen Zhong Ke Rong Electric Information Co., Ltd ) was found in 2008 , we got our register brand Callvi in 2012 . With a desire to supply high quality voice amplifier (PA) to the customers from all over the world .Collectively we have 7 years OEM service experience in PA market .Our workshop more than 2500 square meters , has 4 production lines with 5s management , annual output more than 2 million sets .As one of the leading manufacturers in china , we have won high reputation with customers from over more than 20 countries and regions worldwide ,especially customers from European and American markets . Our Goal is to be your loyal partner not just the supplier .If you choose Allah , you will choose profession and reliability .As you as you have requirements for voice amplifier or PA system , pleas feel free to contact me .