Air Line is sold by the foot (12 inch) increments. Choices include 1/4" air line and 5/32" air line. Most rear air ride kits utilize 1/4" air line and most front cartridge set up utilize 5/32". Please choose air line size and quantity that you need. Quantity of (1) will be 12", quantity of (2) will be 24" and so on.... 
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