So many of these tanks look so close that they are hard to tell apart.  This one does not have a vent tube on the top.  The fuel outlet on the bottom is a curved nipple you would attach fuel hose to.  If you hold the tank upside down with the widest part of the tank toward you… the bottom right of the tank angles down, perhaps to clear something on the scooter.

Tank description:

• Tank width: 30cm (12.0 in) including tabs 
• Tank length: 27cm (10.63 in) including lip
• The bolt holes on the side are 162mm (6.4 in) apart center-to-center
• Nipple on bottom
• Tank height without cap nipple at tallest point: 17cm (6.7 in)
• Hole on top of tank (28mm diameter) along with the gas cap neck hole (43.5mm OD)
• No vent tube on top of tank 
• Metal
• Inlet for cap is not threaded.  Uses a push and twist-a-half turn cap.
• Cap not included
• Compatible with 50cc-150cc 4 stroke

• All measurements are approximate due to the difficulty in measuring the unusual shape of the tank. Please use the pictures and approx. measurements to match your tank.

  Cap link:

  
  Chinese Gas Fuel Tank Cap – 36mm – Version 16

  This tank fits 50cc scooters including the Tao Tao Blade 50, Classic 50, Jet 50, Pony 50, New Speedy 50, Speedy 50 and Thunder 50.

  Shipping details:

  Do you need your gas tank fast?  If you order before 3:00 pm CST, Monday thru Friday, your order goes out the same day.  Buy now!