(indiscernible). >> here he is sitting next to a model of a bomb. he bought it in pakistan with north korean's help. a similar design would emerge. >> his claim is that he was doing things at the bid will of successive civilian military governments in pakistan. >> simon henderson is a receipt van journalist he has known and written about it for 25 years. he received this plaque from kahn of a spinning sent fuj critical to iranian enrichment. >> it is a fast moving cylinder. think of it as a top loading washing machine important to balance if you don't balance it properly it makes a dreadful noise and could shatter.