Bsnl mobile operator is one of the biggest mobile operator in India. But it should work on their network. I used this sim for 2 years but I cant use it any more because of its network problem. Sometime the network shows full but the opposite parties says that they cant hear clearly when I call them. It offers are good and I would like to use this sim as it is a Indian company and is there from many years but the only problem is with network. They should work on it as soon as possible because the other companies are launching 4g.