The SMC Pentax-A 35-80mm f/4-5.6 is a compact manual-focus standard zoom Pentax sold as a low-cost kit lens for its KA-mount film SLRs. Bearing the A-series designation, it carries the electronic aperture contacts needed for program and shutter-priority auto exposure on bodies such as the Program Plus and Super Program.
Optically it uses 7 elements in 6 groups behind a 49mm filter thread, with a 6-blade automatic diaphragm running from f/4-5.6 to f/22-32. Minimum focus is 40cm, giving roughly 0.25x maximum magnification. The barrel measures 65 x 58.2mm and weighs about 185g, with a rotating front element and SMC coating.
Handling favours simplicity over speed: the zoom and focus rings are light plastic assemblies typical of Pentax's budget consumer line rather than the metal-barrelled A-series primes. Contrast is modest and corners soften wide open, but the lens stops down quickly to usable sharpness for snapshots and travel work.
On the UK used market this lens turns up cheaply, often bundled with K1000 or Program-series bodies. Buyers should check the aperture ring clicks smoothly through the A setting, confirm the diaphragm blades snap shut without oil staining, and inspect the plastic mount for wear since it lacks the durability of Pentax's metal-mount primes.