No ROM connection on the adapter. Diaphragm control of the lens is set manually. Automatic diaphragm, auto-focusing,or any other functions will not operate correctly while using this adapter. "Stop-down mode" will need to be used when metering since the lens does not have the ability to have its aperture controlled by the camera body. Made of Aluminum. Compatible For All T2 Lenses Olympus 4/3 Camera (E-1 E-3 E-5,E-10 E-20 E-30,E-520,E-420 E620,E550,E510,E450,E410,E400,E300,E100etc) Package includes: T2 Lens To Olympus OM 4/3 Mount adapter X 1Unbranded/Generic