Check the listing for details. Vintage Sylvania Blue Dot Flashcubes 4 Flash Cubes. Made in United States. Listed at 9.99 USD. The Vintage Sylvania Blue Dot Flashcubes are a set of four flash cubes designed for use with Sylvania flash units. Made in the United States, these flash cubes are compatible with a universal range of brands and are ideal for creating a vintage or retro lighting effect. The blue dot design adds a unique touch to the flashes, making them a stylish and functional addition to any photography setup.