Pentax K lens mount

Yes
48.0
45.5

Pentax introduced the K-mount in 1975 for full frame (35 mm) sized film cameras, then evolved in a lot of variations essentially for electonic communications between camera and lens (KF, KA, KA2, KAF, KAF2, KAF3, KAF4) - details in this article.

The K-mount is used in lenses for both full frame and APS-C sensor cameras.

An interesting article on K-mount evolution is at this link.

NameSensor formatSensor crop factor
K
Full frame1.00
KA
Full frame1.00
KAF
Full frame1.00
KAF
APS-C1.52
KAF2
APS-C1.52
KAF3
Full frame1.00
KAF3
APS-C1.52
KAF4
Full frame1.00
1620