The Spektrum Smart Battery Checker and Servo Tester is a must have tool for any pilot or driver's toolbox. This battery checker and servo tester has even more functionality than previous generations. More than a battery checker, it features a built-in cell balancer, PWM checking, a voltage checker for receivers that graphs voltage over time, integrated servo tester and driver, connections for IC2, IC3, and IC5, and Spektrum Smart battery connectivity.