As with all 3D puzzles Ravensburger, the longest is to sort the pieces numbered. When done, the installation is fast. About 1 hour for a 9 year old child. The building holds well, think however, to bend slightly to remit duties, intermediate gold plastic pedestals. We mistakenly imagine, the LEDs on the tower or the LEDs 3 in number are on a case which came bottom of the tower. it takes 3 AAA batteries (not included). The 3 LEDs do not light up simultaneously. You have to press a small button on the base, to alternate 2 yellow LEDs and the central LED that it is multi-colored (red, blue, green, yellow). As lighting is from below, the light effect is smaller than the pictures illustrating the puzzle box.
