Purchased to run in a Granite 4x4 3s, and they just fit in the battery compartments. Balance leads could be a tad longer, but that can also lead to issues of where to place the wiring when the battery is in use. Run time was about 40 minutes, and lots of it was wide open runs, or bashing through rough terrain and longer grass/sticks. This is my 3rd purchase of Ovonic Lipos, and I will certainly buy again. They balance out well, wiring seems decent, and run times seem on par with more expensive packs.