• High-quality sweatshirt that is heavy enough to endure the cold as well as the years
• Front pouch pocket, matching drawstring and rib cuffs
• Note: If you like your hoodies baggy instead of the perfect fit, go a size or 2 up
• 50% cotton and 50% polyester
• Preshrunk to minimize shrinkage

On October 1, 1998, Sailors serving as Ocean System Technicians were merged into the Sonar Technician rating. us navy e7 ocean systems technician (ot) blue rating badge The fact that sound travels quite well under water—and faster than it does through the air—was one of the reasons that sonar (SOund Navigation And Ranging) was developed as a submarine detection device. On November 26, 1969, the Secretary of Navy approved the establishment of the Ocean Systems Technician rating (OT).