These Image Series chopper tanks are real smooth looking pieces of art and really complete the smooth looks of North Sea Chopper frames or other frames with a 4" stretch in the downtubes, 3" minimum backbone stretch, and a top tube not exceeding 1 1/2" in diameter. The tanks come with weld-on mounting brackets, which are recessed in the bottom of the tank for a smooth hidden look. Tanks are tapped 1/8"-27 NPT at the rear of the tank for the fuel crossover line, and must be used with a 13/16" (22mm) petcock. Capacity is approx. 5.2 gallon (19,7L.) for the shortest version. Tanks are supplied complete with your choice of a flush mount or raised bung chrome pop-up gas cap. The 6" stretched version is also available for use with a stock style screw-in type gas cap.