ribbon. The medal was awarded with a certificate and was worn on the left upper chest. Uniform regulations specify when the medal or ribbon bar was worn. Wear of this medal on the ribbon bar was mandatory. Medal variations Several distinct variations of each grade of this medal exist. Although established in 1956, the first 10-year medals were not manufactured until 1959; the first 15-year medals in 1960 and the first 20-year medals in 1965. Because the practice of serial numbering medals was discontinued in 1959, only the Faithful Service Medal in bronze exists in a serial numbered version. According to research by John Standberg the different types are; 20-Year - Gold Type 1 - (1965–72) Silver "900", gold-plated, flags on the obverse are enameled. The silver content stamp is below the crossed laurel branches on the reverse. Type 2 - (1973–74) Bronze, gold-plated, flags enameled. Type 3 - (1974–75) Bronze, gold-plated, flags lacquered over a pebbled finish Type 4 - (1975–76) Same, lacquered over a smooth finish. Type 5 - (1977–83) Same as type 4, with" -UND-", 34.7 mm in diameter. Type 6 - (1983-86) Same as Type 5, 35 mm in diameter. Type 7 - (1986-90) Same as Type 6, grain stalks in the NVA emblem are stylized and closed. 15-Year (Gold) Type 1 - (1960-63) Silver "900", gold-plated, content stamp on reverse above the intersection of the crossed laurel branches. Type 2 - (1964–72) Silver "900", gold-plated, content stamp is below the crossed laurel branches. Type 3 - (1973–74) Bronze, gold-plated. Type 4 - (1974–76) Bronze, gold-plated with outer ring around State Seal on the GDR flag on the obverse. Type 5 - (1975) Same as Type 2, but with outer ring around State Seal on the GDR flag on the obverse. Type 6 - (1977–83) Same as type 4, with " -UND-", 34.7 mm in diameter. Type 7 - (1983–86) Same as Type 5, 35 mm in diameter. Type 8 - (1986–90) Same as Type 6, grain stalks in the NVA emblem are stylized and closed. 10-Year - Silver Type 1 - (1959) Silver "900" content stamp on rim, GDR flag on the obverse without the State Seal. Type 2 - (1960–61) Same as Type 1, flag on the obverse with State Seal. Type 3 - (1962–63) Silver "900" content stamp on reverse above the intersection of the crossed laurel branches. Type 4 - (1964–72) Silver