These Clip on Adjusters come supplied in a pack of 12 and are to be used with the Langham Multi Purpose Chair Raiser, each adjuster raises a chair by an additional 20mm.When used in conjunction with the chair riser these clip on adjusters can raise a chair by a total of 150mm which is the maximum suggested safe height, the wide base ensures that the chair is stable and secure at all times, increasing the users confidence. The Langham Multi Purpose Chair Raiser is also available from this section of the shop.