Internal impedance is a measure of how easily a cell will deliver current. A low internal impedance cell has a low resistance and if you need to pull a lot of current from the pack, the pack's voltage won't drop causing a crash.

With large aircraft, aerobatic aircraft, an aircraft that uses a lot of servos, or with digital servos this is an extremely important factor. We’ve listed the internal impedance for all of our packs and cells so that you can better compare them with other brands on the market. In particular, be very careful using high capacity, but also high internal impedance packs in high draw applications as they can cause a crash!