Hume Evolution Cavity Soft Closer Designed for the soft closure of cavity doors, Spring loaded system, can be retrofitted to existing cavity units, Quick and easy to install, The Hume Evolution Cavity Soft Closer is the perfect solution for a soft, safe closure to cavity sliders in the home. This pack includes instruction leaflet, soft closer mechanism and fittings. This Soft Closer is to be used in conjunction with Hume Evolution Cavity Sliding Units Only.