Specifications include, but are not limited to: The partitions should be manually operated, paired panel operable partitions. Panel Construction 1. Nominal 3-inch (76mm) thick panels in manufacturer's standard 48-inch (1220mm) widths. All panel horizontal and vertical framing members fabricated from minimum 18-gage formed steel with overlapped and welded corners for rigidity. Top channel is reinforced to support suspension system components. Frame is designed so that full vertical edges of panels are of formed steel and provide concealed protection of the edges of the panel skin. 2. Panel skin shall be: a. 0.50-inch (13mm) NAUF medium density fiberboard, single material or composite layers continuously bonded to panel frame. Acoustical ratings of panels with this construction minimum: i. 50 STC 3. Hinges for Panels, Closure Panels, Pass Doors, and Pocket Doors shall be: a. Full leaf butt hinges, attached directly to the panel frame with welded hinge anchor plates within panel to further support hinge mounting to frame. Lifetime warranty on hinges. Hinges mounted into panel edge or vertical astragal are not acceptable. 4. Panel Trim: No vertical trim required or allowed on edges of panels; minimal groove appearance at panel joints. 5. Panel Weights: a. 50 STC - 8 lbs./square foot.