Many homes contain staircases that are not bordered by a wall. In this case the Y Spindle aids installation of the pressure-mounted gates to these kinds of staircases. It wraps around the baluster to deliver a secure installation. It can be used on either side of the gate of all Gateway Models. Simply replace the included padded spindles for a Y spindle on as many corners as required. NOTE: For installation of a pressure mounted gate on a staircase, you will need to use a K100 Installation Kit.