Raynox HD-6600PRO(58) 0.66x Wide Angle Lens 58mm Mounting Thread Mounting threads is 58mm Front filter size is 72mm Nominal 0.66X (Actual 0.66X/diagonal, 0.66X/center). MTF 30%. Equivalent to 1890-line/TV(1/4" CCD),2520-line/TV(1/3" CCD).