This kit is in 1/700 scale. It includes 2x KC-737 Aerial Refueling Prototypes. They are connected as a single sprue by wires under the main body of the aircraft. Once the wires are cut the aircraft do not require any finishing. This Military version of the Boeing 737-700 has been altered to have a tail boom for airborne refueling.
According to Wikipedia: "The Boeing 737 Next Generation, commonly abbreviated as Boeing 737NG, is the name given to the −600/-700/-800/-900 series of the Boeing 737 aircraft. It is the third generation derivative of the 737, and follows the 737 Classic (−300/-400/-500) series, which began production in the 1980s. They are short- to medium-range, narrow-body jet airliners. Produced since 1996 by Boeing Commercial Airplanes, the 737NG series includes 4 variations and can seat between 110 to 210 passengers."