Features: The extension tube is designed for Sony mirrorless camera lens mounting at a higher magnification at a closer distance. The adapter consists of two loops of different lengths and can be used alone or in combination. It allows you to use all the shooting modes of the camera and requires exposure compensation.  The closer you zoom in on your subject (making it look larger in the viewfinder and picture). When using an extension tube (10 mm or 21mm) or a combination(10 mm + 21 mm = 31 mm), the focal length of the lens should be greater than the tube length (10 mm 21mm). Tube length: 10mm, 21mm. Material: Built-in Metal Bayonet; Plastic Body. Compatible camera: All Micro 4/3 mount camera; For Olympus EPM1 EPM2 E-PL1E-PL2 E-PL3 E-PL5 E-PL6 E-PL7 E-PL8 E-P1 E-P2 E-P3 E-P5 E-P6 E-M1 E-M5 E-M10 E-M10II E-M10III. For Panasonic Lumix G1 G3 G5 G6 G7 G8 G80 G85 GF1 GF2 GF3 GF5 GF6 GF7 GF8 GF9 GX1 GX7 GX8 GM1 GM5 GM10 GH1GH2 GH3 GH4 GH5. Package Included: 1 x Extension Tube Ring Kit