The globe measures 13 3/8 in. before the neck and 14 1/4 inch including neck. The circumference of the globe is approximately 44 in. or 14.01 inches in diameter. The necks outside diameter measures 5 7/8 in. and measures 5 1/4 in. inside hole diameter. This globe is meant to fit on a 6 in. fitter or ring secured with set screws or a twist lock fixture but please ask about exact measurement of the insert notches to make sure it is suitable for your application. Please check your fixture or existing globe for reference. Acrylic is the type of material that they are made of. These globes are absolutely UV stabilized and resistant to UV rays. Acrylic is a material resistant to weathering and aging and has an exceptional brilliance. The shine does not diminish even after prolonged use, thanks to an optimum surface hardness.