Product Info Catalog Hardware Builders Hardware Springs 7/16-Inch OD x 2-1/2-Inch-Long Extension Spring, 2-Pack 7/16-Inch OD x 2-1/2-Inch-Long Extension Spring, 2-Pack Request a Quote UPC: 38594001332 SKU: 681148 Model Number: C-133 2 Pack, 7/16" OD, Extension Spring, 2-1/2" Length, .047" Wire Diameter, 3.51" Maximum Deflection, 11.5 LB Maximum Safe Load, Polybag.