- 100% comfortSoft cotton
- Double-needle stitching throughout
- Coverseamed neck with lay flat collar
- Tag-free neck label
- Shoulder-to-shoulder tape
- Comfortable rib knit cuffs
- Sport Grey is 99% cotton, 1% polyester; Light Steel is 90% cotton, 10% polyester
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).