The TeleLock TS-90B Speaker Stand collar has an internal one-way friction mechanism with three settings. In the RAISE setting the mechanism grips and holds the tube allowing you to incrementally pull the center tube up to the required height. In the LOWER setting TeleLock eases off and assists lowering the center tube. In the LOCK position the telescoping tube stays in place allowing for easy removal of the speaker. This unique design reduces strain and adds safety.