RTS, 1975-81. AE bayonet lens mount. (1-PX28) Aperture preferred AE, AE compensation, match-needle diodes for manual metering, LED meter display in VF, AE compensation, hot shoe, PC sync terminal, shutter speed range 4 sec to 1/2000, plus B, flash sync at 1/60, self timer. ISO range 12-3200, manual film advance and rewind, multi exposure capability, mirror lock-up, interchangeable focusing screens (RTS series), removeable back, DOF preview. Backs/motors: Pro Motor W-6 (5 fps), and Real Time Winder (2 fps) available. Recommended flash: RTF 540, TLA 20, TLA 30. The first Contax camera, body designed by engineers at Porsche. Aperture info visible in viewfinder.