Mamiya Sekor Super Deluxe wall adapter Optics are pretty decent for

Optics are pretty decent for a lens of this age

but it's a pretty standard 90-degree magnifying viewfinder

with some internal dust and a small circular inner coating spot at the edge of one element which will not affect imaging

with clean glass and diaphragm

so it's not exactly simple

Mamiya Sekor Super Deluxe wall adapter Optics are pretty decent forThe Mamiya Sekor Super Deluxe is a 35mm rangefinder camera with a fixed 48mm f2 Mamiya Kominar lens, full manual control, and rangefinder focusing. There's a meter in here, theoretically, but it's not working: you're on your own for exposure. But the speeds are good, the lens is clean, and the RF patch is clear. New light seals, too.