This is an adjustable extension tube for precise alterations to the back focus of your camera. It uses a T-2 thread and can be used to provide anywhere from 7.4 to 9.5mm of additional back focus. It provides a fine degree of precision control over the back focus of your camera, being adjustable and accurate to 1/20'th of a millimeter. It fits directly to the 30A189 Geo-Optik adapter for EOS to T2 Thread.

TS-30A189B