Spalding Arena View In-Ground Basketball System with 54-inch Aluminum Framed Glass Backboard Residential in-ground basketball system easily adjusts rim height from 7 to 10 feet Steel-framed tempered glass backboard, measures 54 x 36 inches (0.5-inches thick) Competition-style 4 x 5-inch rim with 180-degree flex action One-piece steel square pole--5 inches square, made of 3/16-inch steel Authentic Arena View main court backstop look with four-corner Z-Arm mount