This is a classic modernist barware coaster set made by Walther Glass (West Germany) around 1970. The crystal base has concave dots of colored glass, green and amber yellow, set in a circular pattern. This set is new, never used. The set box, not included, fell apart. Each coaster measures 3-7/8" round with the inset able to hold glasses up to 3-1/4" round. The raised outer rim is 5/8" high. Condition is like new.