Eight position pinhole turret with integral shutter. Shutter is cable release activated. Machined in the USA by Abelson Scope Works out of aluminum the turret is designed to fit a Copal 1 lens board hole. Accepts any 3/8″ diameter pinholes, slits or zone plates. Includes 10 pinholes, retaining ring and instructions for use and installation. Overall size is approximately 2″ x 3.25″ x 0.5″.