Install your wake tower speakers using the Universal Fixed Wake Tower Brackets. These brackets are designed to securely fit a range of wake tower pipes. Inserts are included to suit: 63.5mm / 2.50\", 60.3mm / 2.37\" (NPS 2\"), 57.2mm / 2.25\", 50.8mm / 2.00\", 48.3mm / 1.90\" (NPS 1-1/2\"), 42.2mm / 1.66\" (NPS 1-1/4\"), 33.4mm / 1.31\" (NPS 1\") wake tower sizes.