Wolo 853-800 Philly Express Pro Truck Train Horn and High Pressure System 130 Decibels - 290/421/548/648 Hz Horn size: L 15 in. x W 5-1/2 in. x H 6 in. Compressor size: L 6-1/8 in. x W 3-1/2 in. x H 5-1/8 in. Tank size: L 9 in. x W 5 in. x H 5-3/4 in. Tank capacity: 2.5 liters