‘- Accessory clamp for use with WS/550, WS/640 & WS/650 multifunction “t” stands – Required to attach to any one of the four legs of these stand models the following accessories: QLX/4 Telescopic mic boom – QLX/5 Sheet music holder – IPS/11 iPad holder – IPS/13 Universal tablet holder – LPH/X Laptop holder.