Single-leaf Torsion Bar Spring Mounted in Frame (Model No. R)

• Enclosed coil spring mounted in the hatch frame assists operation
• Automatic hold-open arm
• Opens to full 90°
• Sizes from 3' x 2'6" to 4' x 4'
• Steel and galvanized prime painted
• Supports 40 psf live load
• Cover has 1" of efficient insulation to provide U-value of .17 (Optional 2" insulation offers a "U" of .09)
• Cover "R" value is 3.7 and curb "R" value 3.13
• Zinc or cadmium plated hardware