The Baader C-NOSE is 1" (25.4mm) C-Mount Adapter with 1.25" Nosepiece. Threaded to hold mounted 1.25" filters (M28.5) on to the front. Or you can also sleeve mount an unmounted 28-mm diameter filter firmly into the internal sleeve.
|C-Mount Adapter||1" / 25.4mm|
|Nosepiece||1.25" / 31.75mm|
|Insertion Length||18mm / 0.70"|