Tour Grade Speaker stands utilize a variety of adjustable features for easy set up and tear down during live performances. Ergonomic knobs are located in two areas for adjusting both the spread of the tripod base, and the overall height adjustment of the stand. With four positions to choose from, you can adjust the height of your speakers as needed, and a locking pin guarantees the speaker stays at the height you choose. The actual speaker pole can perform double duty and accomodate both 1 3/8 Inches , and 1 1/2 Inches housed speaker mounts.