Product Info Catalog Hardware Builders Hardware Springs Extension Springs, 3/8-In. OD x 4-1/2-In., 2-Pack Extension Springs, 3/8-In. OD x 4-1/2-In., 2-Pack Request a Quote UPC: 38594002094 SKU: 681379 Model Number: C-209 2 Pack, 3/8" OD, Extension Spring, 4-1/2" Length, .028" Wire Diameter, 12.9" Maximum Deflection, 2.39 LB Maximum Safe Load, Polybag.