PENTAX Super-Multi-Coated TAKUMAR 135mm F3.5 Takumar M42 mount Although listed as Pentax K mount, it is an M42 mount. Aperture, AUTO/MAN switching, and ring operation are smooth and without problems. Some dust and debris may be present, but there appears to be no mold or haze. Please understand this is based on a layman's assessment. One-owner item, in good condition, but please be aware of age-related deterioration. Focal length...71-150mm Open F-value...2.9-4