Baader DSLR-2 Filter Holder M48/SP54.
In order to ease the adaptation of Baader 2" filters onto most camera lenses, we produce a general adapter, to convert from the ASTRO-2" Standard (M48) into a more common photo-standard of SP54 mm.
This ring is named: DSLR 2" FilterHolder M48/SP54 (item B240 8166).
Individual lens adapters for most camera-lens threads are available to fit onto this (B2408066) Filter-Holder - namely: M46 (B2958046) / M49 (B2958049) / M52 (B2958052) / M55 (B2958055) / M58 (B2958058) / M62 (B2958062).
Larger lens threads may be utilized by adding another 62 mm stepper-ring: M62/M67 (B2968067), M62/M72 (B2968072), M62/M77 (B2968077), M62/M82 (B2968082).
This is how it works: The lens thread adapter (in this case M62 or M55 or M49) fastens onto the camera lens, next comes the Filter-Holder M48 (B2408066) and lastly any 2" (M48) Baader-filter will thread onto the assembly.