Bases included. Tungsten alloy sphere is 1.5kg/3.31lbs. Aluminum is 0.25kg/0.54lbs. Both are 2.175" diameter. Tungsten is a high density element and surprisingly heavy when compared to the aluminum. The set is a great conversation piece. Includes certificate of chemical composition and interesting tungsten facts. Machined from aerospace grade tungsten, these spheres are an excellent contemporary addition for your desk at work or side table at home. Surprise your colleagues and friends with the spheres' differences Tungsten is one of the densest naturally occurring elements, and now you can add one of nature's wonders to your own collection. If you like the sphere, don't forget to check out our Tungsten and Aluminum Cube Sets.

• Make sure this fits by entering your model number.
• 1 Tungsten sphere with 1 aluminum sphere
• Great for desks or gifts
• Perfect for teachers