westin white tea home diffuser refill cartridge - signature white tea scent westin refresh your home with the westin white tea scent system. simply insert a scent cartridge, plug in, and enjoy. with its compact design you can conveniently mount it to a wall, place it on a table, or tuck it in a corner. it effectively freshens up to 800 square feet of your home and each scent cartridge lasts approximately 300 hours.