[Exquisite workmanship] Well-finished black wooden case, quiet and generous, nylon strings and stainless steel frame, tough and durable, 46g each metal ball which can ensure a long swing time [60 Seconds Swing Time] The heavier the ball weight, the lower the friction between the balls can be, the longer the swing time, the total weight of the balls is about 260g which can swing up to 60 seconds [Simple installation] Just put the frame into the hole of the wooden case, then will finish the installation, the finished production dimension is about 18*12*18cm (L*W*H) [Versatile Items] Due to its fun way of playing, every child is very easy to be attracted to Newton's Cradle, a nice gift for them; and as an office desktop decoration, it can help you release a lot of pressure when seeing the swing ball [No mess with tangled cords] Unlike the competition, everything is neatly packaged and secured in place to ensure the ropes will be tangled on arrival