Globes 6 inches in diameter with a 2.81 inch minimum neckless opening and up to a 4.5 inch maximum opening. They are white acrylic, injection blow molded, water and shatter resistant with UV inhibitors to help prevent yellowing. This is a custom cut and is not returnable. To request a custom opening, please enter the opening desired in the comments section at the bottom of the checkout page, or call 800-665-3594. If no custom opening is indicated, the globe will be sent with the minimum opening indicated in the description.