The Gator Frameworks GFW-SPK-SP standard sub pole with 20mm adapter included. This All Steel Construction pole with Built-In Safety and Easy-Grip Tension Knob Height Adjustment easily Fits Traditional 1 3/8" and Threaded M20 Subwoofer Pole Mounts. It includes a removable adapter for threaded M20 Mounts and has a Minimum/Maximum Height of 35"/60" (889mm/1524mm). Ships in Signature Frameworks Retail Friendly Packaging. The most efficient and effective way to stack and enhance your PA system with a sub speaker.