Spalding Portable Basketball System - 50" Acrylic Backboard Portable basketball system with 50-inch acrylic backboard Heavy-duty steel frame; Pro Slam breakaway rim ExactaHeight lift system adjusts from 7.5 to 10 feet in 6-inch increments 3-piece, 3.5-inch round steel pole; authentic board pad 34-gallon base fills with sand or water for stability