1.Spare part : (1)4 Suction Cups(2 Top Suction cups+2 Bottom cups,Top suction cups can be twisted (2)2 Rims(Rims use to connected Hammock and suction cup. (3)if you received more parts,it must be backup. 2.Please install this item on smooth surface,it better to keep suctions cups in same Level(2 top+2 Bottom). 3.Exclude air before install suction cups;It’s better to …