This bolster spring kit fits Hendrickson suspension equalizer beam applications, measuring 12 in. long by 10 in. wide with a 12.001 in. height. It ships as one kit per each and supports the bolster plate assembly, helping distribute load between the axle and frame as the suspension moves.Interchanges:4000-641790024000-641790494000-64179264179-00264179-04964179-264179-49DT16100AFeaturesSuspension bolster spring kit for equalizer beam applicationsDimensions: 12 in. length x 10 in. width x 12.001 in. heightSold as 1 EACH per kitTech SpecsLength: 12 in.Width: 10 in.Height: 12.001 in.Unit of Measure: EACH