The 10' of air line is in addition to the wiring harness # 1 and #2 shown in the instructions for Air LIft compressor 25592. We have not had any problems installing the compressor kit on pickup trucks and rear mounted air bags. You should not need any additional air line for the install. Part number 451030A on our website is the 1/4 inch air line that is used in the kit if you would like to order additional air line, but it should not be necessary.