Metabones Speed Booster Ultra 0.71x Adapter for Canon EF Lens to Sony E Mount T Speed Booster Metabones Speed Booster Ultra 0.71x Adapter - Front Cap - Rear Cap - Tripod Foot Key - Metabones 1 Year Limited Warranty Compatibility: Canon EF-mount lens to Sony E Mount T Speed Booster Crop Factor: 0.71x Groups/Elements: 4 / 5 Length: 2.6 x 1.1" / 6.60 x 2.79cm