This is a very popular leaf spring on boat trailers. It is called double eye because it has eyelets for the bolts to go through on both sides. It measures 25 1/4" from center to center straight across on the holes. This particular trailer spring has 3 leafs. The spring itself measures 1 3/4" wide and the inside diameter of the spring bushings is 9/16". This spring has a weight capacity of up to 4,000# for the pair of springs.
We normally recommend that you replace springs in pairs, but they are available individually as well.
