C-mount Flangeback: 17.526 mm
CS-mount Flangeback: 12.526 mm
Canon FD Flangeback: 42.0mm
Konica Flangeback: 40.5mm
Nikon F Flangeback: 46.5mm
Olympus Flangeback: 46.0mm
Pentax “K” Flangeback: 45.5mm
Pentax Screw Flangeback: 45.5mm
Ricoh Flangeback: 45.5mm
Sigma Flangeback: 44.0mm