Product Info Catalog Hardware Builders Hardware Springs Extension Spring, 1-1/8-In. OD x 16-In. Extension Spring, 1-1/8-In. OD x 16-In. Request a Quote UPC: 38594002513 SKU: 681486 Model Number: C-251 1-1/8" OD, Extension Spring, 16" Length, .105" Wire Diameter, 21.6" Maximum Deflection, 31.7 LB Maximum Safe Load, Bulk With UPC.