Rohit you are right and your message help all people save money from cheater.mr Tutu i want to know you from what is your basic educational qualification?do u have not any idea what is drdo?it s government body which aim to discover new weapons and technology for our army.what they do with radioactive products they not interested on it or india govt also not interested in it.the concern department is dae.you say only 4 companies have permission to buy it.you are wrong no company can buy it they only give funding to hold the article real buyer is no company its like reserch body who use this gamma rays for.their research work and discover new thisis.everyday you post 4 drdo company if you again posted it with not proper information then know every things little bit.