With a corporate office, manufacturing facility and distribution center in Springfield, New Jersey, United Window has positioned itself as a leader in the vinyl industry. In addition to being quality vinyl window manufacturers, we are also innovators. We introduced the vinyl Single-Hung New Construction window as well as a Builder Series Double Hung. Features of this fully welded Double Hung Builder's window include a true sloped sill, built-in "J" Channel, Block and Tackle Balance System, Tilt in sashes and Intercept® warm edge technology spacer system. Truly state of the art.