Comes with a center-mounted single “pop-up” gas cap and has a capacity of 3.3 gallons. Tank measures 16 1/2"-long x 11"-wide at widest point. Total length from tip-to-tip of mounting brackets is approximately 20". Tunnel is approximately 2 3/4"-wide x 2 1/2"-deep. Features a 3/8" NPT gas outlet (use CC #’s 12726 or 12727 petcocks) on the center of the bottom right side as well as two 1/4" gas outlets (use CC #’s 632252 or 632253 petcocks) on both sides near the rear of the tank to be used as a crossover line or, for multiple choices in routing your gas lines. Petcocks sold separately.