Whether for law enforcement or public safety officials, Rothco’s Mock Turtleneck is the perfect base layer shirt to keep you warm while on duty. Whether for law enforcement or public safety officials, Rothco’s Mock Turtleneck is the perfect base layer shirt to keep you warm while on duty. The turtleneck’s design features a 100% cotton main body, and collar & cuffs made from a blend of cotton / spandex; providing you with a comfortable fit around your neck and wrists. Each long-sleeve turtleneck is not only great as an undershirt but as a standalone all-weather shirt as well.