This 12″ flat 4-pin trailer plug extension harness features a built-in LED wire connection tester for fast diagnostics and safe trailer wiring. The flat-style plug is compatible with standard 4-way trailer connectors and adds flexibility when extending your trailer wiring setup for lights and signals.

Specifications & Features

• Connector Type: 4-pin flat trailer plug
• Length: 12 inches
• Function: Works as an extension harness and built-in wire tester
• Plug Style: Flat rectangular connector
• Tester Feature: Integrated LED indicators show wire connection status
• Ideal for trailers, utility vehicles, and towing setups using 4-way connectors