you'll have to sift through HK's website until you find one that will fit in the battery tray.
they have dimensions on the product description.
if you are lazy and silly u could get a maxamps one
man they make bad packs!!
E-revo 3.3 conversion, 249kv outrunner, 6s, MMM
the porthole from the noob world an here has been opened!! that's how i got in.