It is a tower made up of ever rotating and shrinking pentagons. 8" tall and a 8" diameter circle acts as the base. Each pentagon is circumscribed within the one below it. The rotation is a quarter of the length of the preceding pentagon's side. Hollowed out and perfect for your next visit to the beach. The first version is just hollowed out in Meshmixer so the inside isnt as clean as V2, which I shelled in Solidworks, so the sandcastle it makes will look just as clean as the model