Wolo 847-858 Siberian Express Pro Train Horn 152 Decibels - 307/347/440 Hz Horn size: L 16-1/2 x W 14-3/4 x H 11 inches Compressor size: L 10-1/4 x W 3-1/2 x H 6-1/2 inches. Tank size: L 17-1/4 in. x W 6-1/2 in. x H 8-1/4 in. Tank capacity: 2.5 gallons