Single Convoluted Air Spring. Designed for Front & Rear Suspension on Mini Trucks, Hot Rods and Most Sport Cars. Perfect for MKIV VW Rear's! 2.0" Compressed 8.5" Extended 5.875" Diameter Bags made from Synthetic rubber to be resistant against Oil and breakdown that will ruin Natural Rubber. Available in 1/2 & 3/8 NPT Ports MADE IN THE USA!