Partsam 4X Red/White 4" Round 12 LED Stop Tail Turn Signal Backup Fog Reverse Brake Marker Lights Flush Mount Universal for Truck Trailer Boat Bus RV Waterproof This listing includes 4pcs 4 ROUND LED LIGHT: 2 Pcs 4 Inch round STOP TURN TAIL BRAKE Lights and 2 Pcs 4 Inch Round WHITE FOG BACK-UP REVERSE Lights Universal for Trucks, trailers, tractors, semi-trailer, Dump Truck, bus, boat, special vehicle,etc. For Heavy Duty trucks like Peterbilt, freightliner, international, Kenworth, mack,etc. Function as: Stop/Turn/Tail Light/Backup Reverse Light LED Marker Clearance trailer lamp. Electronics completely sealed to resist corroosion & moisture; Resistant to shock & vibration, waterproof. Diameter with grommet: 137mm, diameter without grommet: 110mm, height 35mm. Kit components: rubber grommet, come with three pigtails EASY TO INSTALL: Black Wire - Ground; Red Wire - high brightness; White Wire - low brightness. It all started in the summer of 2013 with a simple, with bold idea: make better auto parts. In other words, not just a better auto parts - a better way of doing things. A new kind of auto company that works hand in hand with users to do something amazing, something meaningful. Now PARTSam has grown tremendously to become one of the leading platforms of e-Commerce in the aftermarket auto parts industry. Inventory Management/Warehouse &amp; Fulfillment  With our warehouse located in Milpitas, California, we take care of the inventory management for our products. This saves manufacturers space, time, and headache. Automated Multi-Channel Sales  We successfully advertise our products on multiple platforms and maintain top-rated healthy seller accounts, which keep customers drawn to our products. We are continually expanding our customer base as we add more sales channels. Professional Seller - Customers will deal directly with us in regards to issues and concerns they experience with the products. Manufacturers will not have to deal directly with the individual customers, but will experience the benefits of their business, which is the typical win-win cooperation. Universal for Trucks,trailers,tractors,semi-trailer,Dump Truck,bus,boat,special vehicle,etc. For Heavy Duty trucks like Kenworth Peterbilt Freightliner Western Star Volvo International Mack Paccar and other Truck lights Applications: For any 12V Vehicles, Any applications on vehicles, esp. truck trailer RVs etc.