The black garrison cap was introduced in July 2008 as part of the Navy’s new Service Uniform for enlisted personnel at the rates of E-6 and below. Work on developing the new uniform had begun with the establishment of the Task Force Uniform in 2003, which had as one of its four objectives the creation of a single service uniform that could be worn year-round, replacing the Summer White and Winter Blue uniforms and significantly reducing sea bag clutter.
Basics components of the Service Uniform include short-sleeve khaki shirts and overblouses for male and female Sailors respectively, black trousers paired with a silver-buckled black belt for males and beltless slacks for females, black dress shoes worn with black socks, and of course the black garrison cap. The cap was intentionally designed for wear by male and female Sailors—the Women’s style Blue Garrison Cap had been phased out in October 2002, and the NAVADMIN announcing the new uniform described it as a “black unisex garrison cap”—and was the forerunner of several more significant uniform changes introduced in 2015 with a goal of making uniforms as gender-neutral as possible.