Rollei's full-aperture-metering QBM SLR — the SL350, mechanical, 1974.
The Rollei SL350 was a 35mm film SLR made from 1974 as a more advanced QBM-mount body in Rollei's SL line. It offered full-aperture TTL metering, an advance over the stop-down measurement of the original SL35, and used the Rollei QBM mount with its Zeiss- and Rollei-designed lenses.
It is a single-lens-reflex camera for 35mm film on the Rollei QBM mount. The SL350 used full-aperture TTL metering and a mechanically controlled focal-plane shutter, operated in metered manual, so it can fire without a battery, the cell powering only the meter. It retained a compact form while adding open-aperture metering.
It suits users who want the QBM system with the convenience of full-aperture metering in a mechanical body. The brighter, easier metering compared with the stop-down SL35 makes it more comfortable for general and portrait use.
On the used market the SL350 is uncommon and produced in smaller numbers, and QBM lenses are less common than mainstream mounts. Check the foam seals and mirror-damper foam, confirm the mechanical shutter fires at all speeds without a battery, and test the meter, designed for a mercury cell. Inspect the prism for desilvering, check advance and rewind, and note that repair support for the QBM system is limited.