7 Blade and 4 Pin Tester: MECMO 2-in-1 Towing Vehicle Trailer Light Socket Tester includes both 4 way and 7 way trailer plug circuit tester, universal fits for most truck, helps identify lighting problems of your vehicle end 4-flat and 7-way trailer circuit connectors
Rotatable Indicators Panel: In order to better read the indicators clearly, this 7 pin 4 pin trailer socket tester is designed to be rotatable for both side (twist to 90 for both side) Easily adapts to any mounting positions of you vehicle end trailer light plug
6 Diagnostic LED Indicator: Design with easy-to-read LED light illuminate to test trailer light wire circuit status: confirm the functionality of your vehicle's trailer wiring harness's brake lights, turn signals, taillights, stop, reverse, electric brakes, and 12V (auxiliary power)
Built to Last: Excellent waterproof dual way 4 flat and RV 7 blade trailer light tester is made of reinforced ABS plastic, results in a seamless qualitative look; Brass and tin-plated copper terminals provides well-protection, great corrosion-resistance and conductivity
Easy to Use: Plug and play circuit tester for vehicle-side trailer wiring connection. 7 pin tester plug into your 7 way RV standard car end socket, and the 4 pin flat side tester plug into your vehicle-side 4-prong T-connector harness or 4 wire taillight connector; Simply and effectively test your trailer light harness
Red LED Identification Indicators: MECMO 4 way and 7 way trailer plug tester with indicator diagnostic LED (Red lights) easy-to read signal makes it easy to know if you have a safe vehicle-side trailer wiring connection