1.8 gallon (6.8 liter). Takes 83-up screw type gas caps. Fuel tanks are half way 3/8″ internal threaded and 1/4″ internal threaded on the rear end; on both left & right side. Approx. dimensions: 14.7″ (37cm) long x 8.66″ (22cm) wide. Tunnel width 2″. Depth front 2″; rear 1″. Note: It is advised to pressure test; seal and test fit all tanks before tanks are painted and installed. Some tanks are painted; but this coat is applied for rust prevention during storage only. Note: Dimensions are approximate and for reference only.