This metal ring is suitable to set the correct distance between corrector and camera so that the image field is really entirely sharp.
System M68 – spacer (fine-adjustment) rings, available in thickness 0.3 mm (black), 0.5 mm (red), 1 mm (gold)
Very thin ring for fine-tuning in photography with corrector/flattener
Ring in M68 diameter without threads
Fits between all M68 threads, equals approx. 1/3 (0.3 mm), 1/2 (0.5 mm) respectively 1/1 (1 mm) turn of rotation
Prevents binding between two M68 threaded parts
