Product Info Catalog Hardware Builders Hardware Springs Extension Springs, 5/16-In. OD x 6-In., 2-Pack Extension Springs, 5/16-In. OD x 6-In., 2-Pack Request a Quote UPC: 38594002353 SKU: 681452 Model Number: C-235 2 Pack, 5/16" OD, Extension Spring, 6" Length, .028" Wire Diameter, 11.5" Maximum Deflection, 2.85 LB Maximum Safe Load, Polybag.