The Pentax K-mount, sometimes referred to as the "PK-mount", is a bayonet lens mount standard for mounting interchangeable photographic lenses to 35 mm single-lens reflex cameras. It was created by Pentax in 1975, and has since been used by all Pentax 35 mm and digital SLRs and also the MILC Pentax K-01.

What lenses are compatible with Pentax?

All current production Pentax Digital SLR bodies are compatible with SDM lenses. However the DA* 55mm, DA 17-70mm and DA 18-135mm lenses are not compatible with some older Pentax digital SLR's such as the K110D, first version K100D and earlier models (The K100D Super is compatible, provided it has up to date firmware).

What mount does Pentax K1000 use?

The K1000 has a Pentax K bayonet mount, a type introduced with the K Series. Originally it was usually sold with the budget SMC Pentax 50 mm f/2 lens, and it accepts any other manual focus lens with the K mount. This includes the SMC Pentax, SMC Pentax-M and SMC Pentax-A types.