These clip on sign holders are great for any sales floor. The clamp will allow for signage to be attached to square tubing on the sales floor.This clip on sign holders works with threaded stems for elevation. The clamps ease of application will benefit the sales floor. The sign holders ability to attach to square tubing is great for show casing merchandise. Heres how the system works: 1) Choose size and style of frame that best suits your sign. 2) Decide which type of clamp will work best for your fixture: magnetic, spring, or C-clamp. 3) Complete the holder with the appropriate stem fitting and length.