The specific regs on rings are as follows:
Quote:
6. JEWELRY. Conservative jewelry is authorized for all personnel and shall be in good taste while in uniform. Eccentricities or faddishness are not permitted. Jewelry shall not present a safety or FOD (Foreign Object Damage) hazard. Jewelry shall be worn within the following guidelines:
a. Rings. While in uniform, only one ring per hand is authorized, plus a wedding/engagement ring set. Rings are not authorized for wear on thumbs.
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But what's considered eccentric and/or faddish is somewhat open to interpretation. I personally stick to black for watches and don't wear any jewelry in uniform, but that's also my preference.