Knobs for Astro-Tech (GSO/Orion/TPO) 8" f/8 Ritchey-Crétien Secondary
Fits: Astro-Tech, GPO, Orion (US), and TPO 8" f/8 RCT secondary
Knobs: Black plastic, 16 mm (5/8”) diameter
Threads: Stainless steel
- Two sets of knobs, each with a different screw length, are included with your order. Use the length that fits your telescope best. There should be one or two screw thread turns above the secondary housing. In most cases the dust cover will fit without contacting the knobs.
- If the dust cover cannot be installed because of knob height, you can use a shower cap in its place.