MATERIAL---Durable WOOD base, nylon strings, metal balls, stainless steel frame
SWING TIME---The balls continue in perpetual motion FOR ONLY 15-25 SECONDS due to the resistance of the air and friction
DISADVANTAGE---We can not create a vacuum environment, so the balls will have some space when it is working, but it won t influence the effect of playing
APPLICABILITY ---You can put it on your office desk or your home desk or on your shelf. It will be cool desk toy
AFTER-SALE WARRANTY -- If, for any reason, you are not completely satisfied, please contact us by email so that we may address your concerns
