Because Only for compression springs, there are thousands of sizes. 0.023"x0.315"x0.39", 0.023"x0.315"x0.78", 0.023"x0.370"x0.39", 0.023"x0.370"x0.78", 0.031"x0.315"x0.39", 0.031"x0.315"x0.78", 0.031"x0.315"x2.00", 0.031"x0.37" x0.39", 0.031"x0.37" x0.79", 0.031"x0.37" x1.96", 0.039"x0.315"x0.39", 0.039"x0.315"x0.78", 0.039"x0.315"x2.00", 0.039"x0.350"x0.39", 0.039"x0.350"x0.78".
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