For M42 (M42x1) Lens - Nikon F mount Camera M42-AI M42-F M42-Nikon M45-Nik Macro Lens Mount Adapter Ring for D850 D810 D500 etc. - AliExpress Consumer Electronics
Brief description and possible applications - Baader Planetarium
M45 - The Pleiades | Astronomy Pictures at Orion Telescopes
Amazon.com : Metal M45 Male to M67 Female 45mm 0.7mm Thread Pitch to 67mm 0.75mm Thread Pitch 45mm-67mm Step-Up Coupling Ring Adapter for Lens Filter : Electronics
Kenko M45 MC6 2x Teleplus Teleconverter for Mamiya m645 645 Lens - Victory Camera
Amazon.com : Metal M45 Male to M67 Female 45mm 0.7mm Thread Pitch to 67mm 0.75mm Thread Pitch 45mm-67mm Step-Up Coupling Ring Adapter for Lens Filter : Electronics
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