Alpine Labs Michron N3 for Canon The advanced features are interval ramping, bulb ramping, HDR bracketing & queues 2000 plus hours battery life (replaceable) The product is made in USA It is for Canon 5D, 10D, 20D,30D, 40D, 50D, 7D, 6D, 1D mark II, 1Ds mark II, 1D mark III, 1Ds mark III, 1D mark IV, 5D, 5D mark II & 5D mark III