Minolta X-700 with 50mm f2 lens mount_Konica AR The Canon EOS R is

The Canon EOS R is a compact full-frame mirrorless camera compatible with Canon’s RF mount lenses (sold separately)

or the front

Interior dimensions are approximately 14x32x50cm

you can't directly mount to your camera and expect useful results

Some of the element edges have a variant of "Schneideritis

Minolta X-700 with 50mm f2 lens mount_Konica AR The Canon EOS R isThe Minolta X 700 is a manual focus 35mm film camera with full manual or auto exposure, shutter speeds to 1 1000s, and an easy to read lightmeter. Cosmetic condition is very good, with only light wear from use and handling. Good speeds and metering, new light seals. Includes a Minolta MD 50mm f2 lens.