This ultra-rare Sigma Filtermatic Pentax K mount  lens comes with the original box, instructions and
original Sigma  internal glass filter set set that
allows for pin-sharp IR photography with the included R-60 filter.

The full set includes  Y-52, O-56 and R-60 plus clear (default fitted) Sigma 22.5mm filters.

The optics are in mint condition.  AR coatings are perfect. 

No sleeks, scratches, fungus or haze. They are pristine.

The barrel has no knocks/damage, but given the near 30+ year age of the lens, some of the focus distance numbers 
have worn away...(please see photographs)

Selling as I no longer own any Pentax DSLR bodies (I have moved to the Canon dark-side) 

This old but, very rare bird will not disappoint!