M42x0.75 to 1.25" (M28.5x0.75) Filter Adapter Ring - 3mm for ZWO ASI Cameras & CS Lenses Description: This precision-machined adapter ring is a versatile accessory for your ZWO ASI astronomy camera. It features an M42x0.75 male (external) thread on one side and a standard 1.25" (M28.5 x 0.75) female (internal) filter thread on the other. Key Feature: When this adapter is attached to your ASI camera, it not only allows you to screw in standard 1.25-inch astronomical filters, but it also enables the camera to mount CS-mount lenses for wide-field astrophotography or guiding. Specifications: • Type: Filter Adapter Ring • Thread A (External/Male): M42 x 0.75mm (T-Mount) • Thread B (Internal/Female): M28.5 x 0.75mm (Standard 1.25" Filter Thread) • Optical Length (Thickness): 3 mm • Material: High-quality Aluminum Alloy • Color: Black (Anodized) Compatibility: • Cameras: ZWO ASI series cameras (and other astronomy cameras with M42 female threads). • Accessories: Accepts standard 1.25" filters and CS-mount lenses. Features: • CS Lens Compatibility: A clever solution that allows your ASI camera to use CS lenses when this adapter is installed. • Spanner Holes: Features two small pre-drilled holes on the outer edge, allowing you to use a spanner wrench for easy, secure tightening and removal. • Precision Machined: Ensures a secure, perfectly aligned, and tilt-free connection between your camera and accessories. • Internal Threading: The inner 1.25" female wall is threaded and blackened to minimize internal reflections. Package Includes: • 1 x M42 Male to 1.25" (M28.5) Female Filter Adapter Ring (3mm) (Important Note: Please double-check your equipment's thread sizes before purchasing. You will need an M42x0.75 Female thread on your camera side and a standard 1.25" Male filter thread or CS lens to use this adapter. Cameras, filters, and lenses are NOT included.)