The car horn sound effect controller can adjust 25 horn sounds, allowing you to customize the sound of the car horn. Adjustable volume: equipped with 2 knobs, multiple choices, and simple operation. This controller is made of high-quality Plastic and can withstand the rigors of daily use. The sturdy structure ensures long-lasting durability. Easy to control, easy to install: easy connection, positive and negative terminals, good sturdiness. Designed for worry-free installation, it can be easily connected to a variety of car horns and supports a working voltage of 12-24V. Voltage: 12-24V Colour:Black Material:plastic Package Contents: 1 x Electronic Horn Controller Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.