VTG Staedtler Mars Masterbow Drafting Compass Set German Engineering Tool Kit Staedtler Mars Masterbow drafting set offers professional-grade precision for architects, engineers, and artists. This vintage German-made kit includes a large master bow compass with a center wheel for fine adjustments, a smaller spring bow compass, an extension bar for larger circles, and a technical pen attachment. The instruments are constructed from durable matte-finished metal and come housed in their original hard plastic protective case with a blue flocked insert to keep components organized and secure. Measurements: • Case: 9.5" x 4.75" • Large Compass Length: 6.5" • Small Compass Length: 4" • Extension Bar Length: 6" #Neutral