Servos and wiring can short-circuit, which can damage your expensive radio receiver, battery, and even catch the radio box on fire. The Killer RC inline fuse will prevent this. Just plug it inline between the battery and your on/off switch. Comes with 15A fuse. Works with most any gas or nitro electrical system 3v-24v. In the event of a blown fuse, losing battery power to the receiver can cause a runaway vehicle, so we recommend that you use a Super Bee kill switch™ to stop any potential runaways.