I have for sale a just like new series iii focuser. This comes with a pentax K mount and a mount that is set up for the SAC 7 ccd cameras. It can be adjusted for whatever backfocus your particular device needs. It comes with the focusing screen and also the True-Knife option. This is an excellant piece of equipment, however I have come to the realization that I do not have the skies or patience for astrophotography. This unit is upgradeable to the series IV for a nominal price from Richard at Stellar Technologies. Asking 150 + shipping. Pay-Pal and money orders are ok.
Thaks for looking and Clear skies!!