The Light Ranger Mobile Universal Trailer Tester (MUTT®) is a portable and water resistant trailer light and brake tester that allows the user to perform all testing functions without the use of the vehicle. For 7-way spade, 6-way round and 4/5 pin trailer harnesses, the Light Ranger MUTT® simulates all electrical circuits of standard towing vehicles for boating, RV, landscaping, hunting and similar type light-duty trailers. Included with each tester is a battery charger and 3-way trailer harness adapter.; Features and Benefits: Tests 7-way spade, 6-way round and 4/5 pin trailer side harnesses; Short circuit protection; Turn signal simulation and power verification LED; Water resistant; 500mA Battery Charger and 3-Way Trailer Adapter included; Internal battery compartment (battery not included); Includes: 500mA Battery Charger (#CHR0001)• 3-Way Trailer Adapter (#8000)