Guidons
A Marine guidon is always rectangular, 22 by 28 inches (56 by 71 cm), with a scarlet field and gold lettering, and an Eagle, Globe, and Anchor centered.
Fleet Marine Forces units have "FMF" emblazoned above the EGA, reserve units display "USMCR", and all others have "USMC". The regimental level numeral will be displayed in the lower left corner, unless a higher or lower command numeral provides better identification (for example, a battalion's headquarters company would display that battalion's numeral instead of the regiment). The company-level designation letter, abbreviated title, or number will be in the lower right corner.
No additional attachments are authorized, including streamers, bands, or the like. Some units incorporate additional banners or mascots into unofficial guidons.
Guidons are used in the same manner as colors for a company- or platoon-sized unit. Much like the colors, the guidon represents the unit commander. It is entrusted to the unit guide for parades and ceremonies, and displayed in or near the commander's office when he or she is present.
Guidons are also used in recruit training to identify individual platoons. First and second phase platoons have a gold background with their four-digit platoon number in scarlet, while third phase platoons have a scarlet background with gold lettering and trim. The guidon is used as an aid to instilling unit identity and pride, representing the platoon. Some drill instructors will test that pride by attempting to dishonor the guidon and expecting the recruits to intervene. Also, the recruit assigned to carry it, the guide, is treated as the most senior recruit of the platoon, and uses the guidon to marks the line of advance in close-quarters drill.
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