This
device when fitted to the 8x magnifier (68125) enables you to view and check
the 35 mm roll film while marking the desired frame by depressing the puncher
(located on the side of the device). The puncher punches out a V-shaped piece
of film on the perforation to mark the frame. When fitted in the reverse position
to the 8x magnifier, you are able to view and check the slides.