Keltron is an electronics development corporation established by the Kerala state government in 1977. It has four business units: control and instrumentation, pneumatic products, information technology, and strategic services. The strategic services group manufactures towed array systems for defense applications. A towed array is a long cable with hydrophones trailed behind a ship to detect submarines and missiles. It allows detection over long distances, though positioning of the hydrophones must be continuously monitored. The internship report summarizes the student's two week training at Keltron, during which he learned about the company's departments and products like towed arrays and computers.