I use one of these: http://kaidomain.com/ProductDetails.aspx?ProductId=10995 And one of these: http://kaidomain.com/ProductDetails.aspx?ProductId=6653 For a total of 4.2ma I have also used these on XML with higher voltage. http://www.dealextreme.com/p/8-4v-sst-50-5-mode-memory-circuit-board-for-flashlights-50025 Also read this: http://www.candlepowerforums.com/vb/showthread.php?273787-Mag-switch-and-AMC7135-drivers