Pandora-6, optical converter for 8mm cine camera 
"Quartz 1x8C-1"
M25 mount, s/n 7206450
Krasnogorsky Mechanical Plant, USSR

Very good condition. Lens is clear and does not have any fungus or scratches. Inside there are microspecks of microdust. Ring rotates properly and has a small backlash. Body has small signs of age. Filter carving has a dent.

This is part of "Agat-6a" lens system from 8mm cine camera "Quartz 1X8C-1"  which consisted from lens "March-1" and this lens "Pandora-6".
"Pandora-6" was in fact a focusing part of the lens providing change of focal distance from 9 to 23 mm with constant 1:1.8 lens speed.

Characteristics:
Lens s/number - 7206450
Frame size - 8 mm
Limit of aperturing - 1:1.8
Type of thread - M25
Dimensions (mm): 54*54*53
Focal distance - 9-23 mm.
Mass - 207 g