Authorized on May 18, 1921, and awarded on a selective basis to enlisted personnel of the Coast Guard and Coast Guard Reserve for periods of three year's above-average continuous service. Recipients must have been recommended by their commanding officer for proficiency in rating, sobriety, obedience, industry, courage and neatness throughout the period of service. The original medal was about 20 percent larger than the present award, and had a top suspension bar with the words, "U.S. Coast Guard." Additional awards were indicated by a wide clasp with the name of the ship or station engraved upon it, but this has been replaced with a star for additional awards.