This is the Hitec Digital Servo Field Programmer and Tester. FEATURES: Manual and automatic test with receiver pulse width and receiver voltage measurement for any brand of servo Tests servo speed, dead band width, rotation direction, fail-safe and position program for Hitec digital servos Tests overload protection and resolution mode select of Hitec G2digital servos Also tests overload protection of Hitec digital micro servosPowered by a 4-cell 4.8V NiMH AA size battery pack (included) that can be recharged with any peak charger capable of charging at about .06A-1.0A INCLUDES: Hitec Digital Servo Field Programmer and Tester with Instructions REQUIRES: Connecting to receiver and servo SPECS: Dimensions: 5.8 x 2.8 x 0.79" (148 x 71 x 20mm)