Scooby Doo!
SD is on his collar.
SD
SD Gundam Force
The only one I know of is Megas XLR or maybe SD Gundam.
I really don't have a clue sorrii :'(
Skeeter Davis Sammy Davis, Jr
SD stamped on a ring could refer to the manufacturer's mark, indicating that the ring was made by a company or jeweler with the initials SD. It could also stand for "Sterling Silver," indicating that the ring is made from 92.5% pure silver.
14K is the content of gold in the item, and SD is most likely the initials of the ring's maker.
Cartoon network has aired most of the gundam series. GundamGundam 0080 & 0083G GundamGundam Wing i believe even 8th MS Team and SD Gundam
An Australian 2-cent coin from 1966 with the initials "SD" (for designer Stuart Devlin) missing is known as the "missing SD" variety. This coin is considered a rare error and can be valued significantly higher than its face value, often fetching prices between AUD 1,000 to AUD 2,000 or more, depending on its condition. Collectors and numismatists are particularly interested in such varieties, making them sought after in the coin market.
Generally speaking, members of the Gestapo wore civilian clothing unless they needed the protection of a military uniform when working in operational areas. In that case, they wore an SS uniform in field-grey colour. Their rank was indicated by police-style shoulder straps, and by their SS-equivalent rank insignia worn on the right-hand collar patch. The left hand collar batch was plain. On the lower left sleeve, they wore a black diamond, outlined in silver thread, bearing the initials 'SD'.
The only two that spring to mind for that era are: Skeeter Davis and the Australian -Slim Dusty.