How do I create and top and bottom surface on this 3D shape

xtailhorizontal = [0 30 30 -30 -30 0; 0 30 30 -30 -30 0]; ytailhorizontal = [55 65 70 70 65 55; 55 65 70 70 65 55]; ztailhorizontal = [58.5 58.5 58.5 58.5 58.5 58.5; 55.5 55.5 55.5 55.5 55.5 55.5];

surf(xtailhorizontal,ytailhorizontal,ztailhorizontal)

Currently, this only colours the surfaces on the side of the shape and not the top and bottom. Is there a way to make the top and bottom surfaces fill as well in the same function?

Thanks