... 4.5gal,horizontal Portable type Ingersoll Rand Ingersoll-Rand Portable Air Compressor P1IU-A9, Twin Stack, 2HP, 4.5 Gal Ingersoll ... approved. Measures 21"L x 15"W x 17"H. 1 Year Limited Warranty. Includes 2 pints of compressor oil. CAPACITY GALLONS4 ... Number634158CFM @ 100 PSI4.3 Ingersoll-Rand Portable Air Compressor P1IU-A9, Twin StaIngersoll-Rand Portable Air Compressor P1IU-A9, Twin Stack, 2HP, 4.5 ...