In May 2008 Boeing began work on the first Boeing Business Jet 3 (BBJ 3), a new, longer-range jet based on the Next-Generation 737-900ER (extended range), which entered commercial service lin 2007. Employees at Boeing are pictured assembling structural wing spars in Renton, Washington. After the wings are sealed, pressure tested, painted, and their systems installed, they will be mated with a pair of fuel-saving, emissions-reducing Blended Winglets. Employees will affix the completed wings to the fuselage just prior to the airplane joining the highly efficient 737 moving line in Renton's Next-Generation 737 final assembly building.