Midwest Photo Metabones Canon EF Lens to BMPCC4K Camera T Speed Booster XL 0.64x Adapter
Amazon.com : NEEWER EF-EOS M Lens Mount Adapter 0.71x Autofocus Speed Booster Compatible with Canon EF Lens to EOS M Series Camera EOS M M2 M3 M5 M6 M10 M50 M100 M200
Amazon.com : VILTROX EF-M2II 0.71x Speed Booster, EF to Micro 4/3 Focal Reducer Booster Adapter Auto-Focus for GH6 GH5M2 BMPCC 4K GH4 GH5 G100 G95 G85 OM-1 EM-1 E-M1X E-M1 iii E-M5