Spalding NBA Portable Basketball System - 54" Glass Backboard Portable basketball system with 40-gallon capacity base for water or sand Tempered glass backboard, measures 54 inches wide (0.25-inches thick) Heavy duty solid steel Arena Slam breakaway rim Three-piece, four-inch square pole with 4-strut mount for increased support Screw Jack adjustable height system moves the basket from 7.5 to 10 feet high