Canon’s first circular fisheye dates from 1971. It has chrome breech ring and no s.s.c. marking on the barrel, but it’s multicoated, for sure. It does have inner filters, SKY, Y3, O, R, CCA4, CCB4.
Like Minolta 7.5mm it’s a fixed focus lens. The only two controls you will find on the barrel are aperture and filter. It’s a beautiful object that really feels solid in your hand, small and heavy, feels very good on Canon camera of its era. Just like handling a fast 50mm. No mirror lock-up is necessary to mount it on your camera (like 7.5mm Nikkor).
Canon Fish-Eye Lens 7.5mm f/5.6
first non ssc version chrome ring