Spalding NBA In-Ground Basketball System - 52" Acrylic Backboard 52 x 32 steel framed acrylic backboard. 3.5MM thick acrylic backboard for superior rebound. Pro-Glide lift system adjust rim height from 7.5 to 10 in 6 increments. Three Piece, 3.5 round steel pole allows for maximum stability. Ground sleeve anchor system allows for easy installation. Backboard has 16 offset from pole. Pro-Slam Breakaway rim and authentic style blow-molded backboard pad included for recreational level of performance.