Ark was a Japanese company that produced a series of die-cast metal monster toys sold under the brand name 'Arklon.' It was originally founded as a sales and marketing subsidiary of famed Japanese toy manufacturer Bullmark. After Bullmark's bankruptcy in 1977, Bullmark co-founder Saburo Ishizuki took charge of Ark and turned it into a full-fledged toy manufacturer. Ark released a variety of toys during the mid-to-late 1970s, including die-cast, soft vinyl, and inexpensive plastic toys. The Arklon toys were imported to the United States by the Marukai Trading Company.
With one exception, King Kong (sold under the generic name 'Mech-Gorilla' in the USA), all of the Arklon toys were based upon kaiju characters from the Ultraman television series. The unique designs, which Ishizuki has described as 'my attempt to create character toys that could be enjoyed even by those unfamiliar with the given film or television series,' have made them favorites among Japanese toy collectors.
What's it worth? Take a look at this Arklon price guide: sold listings for a value indication.