Assembly Needed: The 4 feet large light up numbers are pre-cut into several parts and you need to assemble them before your party begins. A.Match the numbered slots on the board in order with the frame. B.A hot glue gun (NOT INCLUDED) is needed to make the pre-cut frames more stable. C.Screw the bulbs into the holes and put 3 AA batteries (NOT INCLUDED) to the battery box. Ideal Birthday Decoration: This mosaic numbers set is made of FOAM BOARD, a perfect party decoration for anybody's 15th birthday or decades anniversary of weddings/companies. It features with block design, white frames and warm bulbs.