EF-M2 mount adapter is designed to allow for Canon EF mount series lens to be used on M4/3 camera. Plus 0.71 based on the original focal length (equivalent focal length=focal length x0.71), which help enlarge 1 level aperture. Build-in 4groups, 4pcs optical glasses, AF(auto focus) and adjustable aperture, etc.   Features: Gold-plated electronic contact, Auto-focus function.  It can realize AF, adjustable aperture from camera body to lens's aperture.  More durable metal material.  Allow for Canon EF mount series lens to be used on M4/3 camera.  Focus length multiplier: 0.71x.   Specifications: Model: EF-M2;  Compatible Lens: For Canon EF mount series lenses;  Compatible Camera: For M4/3 series cameras;  Focus Mode: Auto focus;  Focus Length Multiplier: 0.71x;  Optical Glasses: 4 groups, 4 glasses;  Tripod Socket: Cu 1/4" * 1;  Diameter and Length: Φ67mm×25mm;  Front Cap: Camera cover;  Rear Cap: Lens dust cap;  Item Weight: Approx. 138g / 4.9oz (excluding cap);  Package Size: 11 * 10 * 6cm / 4.3 * 3.9 * 2.4in;  Package Weight: 310g / 10.9oz;   Package List: 1 * EF-M2 Mount Adapter;  1 * Front Cap;  1 * Rear Cap;  1 * Hex Wrench;  1 * Cross screwdriver;  1 * User Manual ;   Note: It is normal that it is a bit loose when the lens mount adapter is installed on Panasonic camera and a bit tight on Olympus camera.  Camera and lens are not included.