There are three wires. The Green wire is for positive driving mode, the Red wire is for positive brake-light mode and the black is for negative (ground).

All the mounting brackets, screws, and harness are included in the package.

Features:
Weight: 138.5g
Size: 12 x 8.7 x 5.5 cm (L x H x W)
Housing Color: Black
Lens Color: Red and Transparent (It will be sent at random)
No. of LED: 12
For 12V only.
Attractive triangular design and adjustable bracket that fits around the backside of your bumper.

Easy to install.
These extra brake lights improve safety while driving allows your vehicle to be seen quicker when you brake.
Greatly improves reaction time of oncoming motorists and reduces risk of traffic behind you running into you.
Bright LEDs consume far less power than a standard bulb while maintaining optimal light output.
Enhance safety with flashing LED.
High Quality LED, Long Lasting and Very Bright.
All Wiring are Preassembled for Easy Installation.