Get from Amazon : http://www.amazon.com/gp/product/B0078G8B9G?tag=wayofcats-20 <br /> <br />Bobs Knobs Celestron 9.25 SCT Fastar Collimation Knobs Secondary C925FST <br /> <br />Bobs Knobs are made from black plastic and are 95mm in diameter or 38 <br />The threads are stainless steel <br />These knobs fit the Celestron 925 f10 SCT with Fastar secondary Recessed into the secondary hous <br />With Bobs Knobs installed your factory dust cover will fit normally <br />When the knobs are installed the rotary secondary cover must remain open No worries though the co :
