HELIOS 44m-4 Lens Canon EOS EF Mount T3 T4 T5i T6 i 7D 6D 5D Mark II III IV : Electronics - Amazon.com
Amazon.com : !!NEW!! HELIOS 44-2 58mm F2 Russian Lens Adapter Micro 4/3 MFT Mount Olympus PEN OM-D E M1 M5 MARK II M10 : Electronics
Amazon.com : Fotasy Adjustable M42 Lens to Cannon EF-M Mount Adapter, M42 EFM, M42 EOS M Adapter, Compatible with Canon EF M Mount Mirrorless Cameras EOS M M1 M2 M3 M5 M6
Fotodiox Lens Mount Adapter Compatible with M42 Type 1 Screw Mount SLR – Fotodiox, Inc. USA
Helios 44-3 mounted on Canon 5D. Did I get the wrong adapter? - Photography Stack Exchange