Originally Posted by pyromania

It depends on what M11 you have. The standard M11 accepts a 3 cell lipo and the M11x accepts a 2 cell pack.

I use this pack in my M11. The charge holds for about a month of racing two time a week. Common sense rc also sells a pack for the M11 but it seems they are out of stock.

http://www.amainhobbies.com/product_...onics-M11-MX-3