Innovative Design • Multi-step elevated sill design with drainage hole against water leakage. • connect with double header, fixed transom without using tubular and snap-on base cover. • Delicate insect screen easy to install and detach for cleaning and repair purpose • Top and bottom plastic guides smooth and quite sliding motion. • Added the sound-insulated dense strip design, to assure perfect sound proofing against sudden impact. • No use of open back installation. Less Assembly Time • Use of puncher machine for less time consuming (heavy duty machine, manual process) Price Competitive • The price is the same compare to old traditional section but with lesser assembly time. Less Inventory • Top-rail and bottom-rail are the same. • Double head, sill and jamb is adaptable whether with screen or without screen. • Only 6 section is needed to fabricate a window. 10 years warranty against discoloration of section.