Features: -This chrome-plated appearance, single-speaker horn, will produce a powerful driving sound. -Made of metal to ensure better sound quality, maximum strength and durability. -Perfect and compact solution to enjoy the loud horn sound on all vehicles equipped with 12V system. -Can be mounted on roof, or under the hood. Specification: Product Name: Air Horn Compressor Kit. Material: Metal+Plastic. Color: Chrome. Voltage: DC 12V. Current: 18A. Impedance: 1Ω. Sound Level: 150dB. Operation Air: 15-22 PSI(0.1Mpa-0.15Mpa). Size: 45cm/17.71' x 10cm/3.93' (LxH). Horn Diameter: 9.2cm/3.62'. Fitment: Universal For 12V Car Truck Boat Van Train. Safety instructions: 1. Make sure you never attempt to disassemble the electrical components of this speaker kit. 2. Do not touch any part of the compressor with bare hands immediately after use or during use. 3. Avoid operating this product in areas where there is a risk of falling or being immersed in liquid (water). 4. Do not reach out to touch any components that have fallen or immersed in water. 5. Make sure you set up in a well-ventilated area. 6. Do not blow the horn anywhere near the ears of you or others. 7. Before starting the installation, please make sure that your battery ground is disconnected. 8. Use eye protection equipment during drilling operations. 9. The specific voltage requirement of this speaker kit is 12V DC, so it must be installed on a 12V DC power supply. Horn maintenance: 1. Always keep the appearance of the speaker clean, and all wiring is reliable. 2. Regularly check and tighten the fixing screws of the horn and bracket to ensure reliable grounding. 3. The fixed way of the trumpet has a great influence on its pronunciation. In order to make the horn emit a normal sound, the horn cannot be hard-mounted, so it is fixed on the buffer bracket, that is, between the horn and the fixed bracket, a leaf spring or rubber pad should be installed. 3. Regularly check the output voltage of the generator. If the voltage is too high, the horn contacts will be burned. If the voltage is too low (lower than the rated voltage of the speaker), the speaker will make abnormal noises. 4. When washing the car, do not rinse the horn with water directly, so as to prevent water from entering the horn and the horn will make a sound. 5. When repairing the horn, pay attention to the positions of the metal pads and insulating pads, and don't install them incorrectly. 6. The continuous sounding time of the horn shall not exceed 10s to avoid damage to the horn. 7. Do not put all kinds of foreign objects into the speaker to avoid abnormal noise. Note: 1.We provide clear pictures, measurements where possible. Please check as much as possible to make sure the item is the one that you need. 2. Please allow 0.5-1 inch difference due to manual measurement.(1inch=2.54cm) 3.There are no instructions included in this kit.If you want to know how to use or install it,please contact us by Email.We will provide help as much as possible. Package Included: 1 X Single Trumpet Air Horn 1 X 12V Heavy Duty Air Compressor 1 X 4-PIN 12V/30A Pre-wired Relay 1 X 3/8' OD Air Hose 1 X Mounting Hardware