The On Stage SS7745LOK Subwoofer Pole with Locking Adapter takes the wobble and height problems out of the question. The locking adapter has an automatic response to the weight of the subwoofer. The response takes care of the wobble from any speaker pole system. The adapter expands to fill the gap between the pole and the insert that is causing the wobble. Give yourself some piece of mind while on stage performing, and eliminate that speaker wobble. The shaft length adjustments are from 26 to 37 inches.