Product Info Catalog Hardware Builders Hardware Springs Extension Springs, 3/4-In. OD x 3-1/2-In., 2-Pack Extension Springs, 3/4-In. OD x 3-1/2-In., 2-Pack Request a Quote UPC: 38594001851 SKU: 681312 Model Number: C-185 2 Pack, 3/4" OD, Extension Spring, 3-1/2" Length, .062" Wire Diameter, 5.60" Maximum Deflection, 10.9 LB Maximum Safe Load, Polybag.