I don't have the size, but you should be able to figure it out fairly easily. There were three cushions, the big one you sit on, the one in the back that fits the curvature of the trailer inside body, and the third one goes between those two, and is sized such that the entire space between the front of the gaucho frame and the wall is all coushion.
The middle coushion is attached to the bottom large coushion so it is hinged, and folds up when the gaucho is pushed in, forming the backrest of the gaucho.
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