Have the old Apo-Ronar 480/9 with no front filter thread.
rear lens thread must be 72mm but standard .75 pitch of adapters/filters does not quite match. my depth gauge NFC match with 24 and 28 values. They sold me the wrong depth-gauge. i have no clues until know what is wrong.
NB: unfortunately both inner lenses have a bit of fungus. maybe i am using it with technical pan and ortho-films. and one of the screw outside is lacking. what are they for.
has a lever for filter-holder. Where can we get these? have also a fine old 360/9.