2 Inch to 6 Inch Adjustable Height Pocket Spring Coil Unit for Sofa Cushion Seat and Upholstered Furniture Sellers High-quality 1.8mm diameter steel pocket spring coils designed to provide excellent comfort and support for sofa furniture manufacturing. Product Specifications Specification Details Product Name Pocket Spring For Sofa Material High Carbon Steel Wire Wire Diameter 1.0mm-2.3mm Head Diameter 4-6.5cm Middle Diameter 4.5-7.5cm Height 4cm-15cm Turns 4-7 Turns Coils