100% Waterproof Mattress Protector Premium Polyester, Toweling Surface Vinyl-free with Life Time Warranty by The Duck And Goose Co - Twin XL Vinyl Terry:80% Cotton,20% Polyester; Lining:Polyurethane; Sides:Polyester The skirt with elasticized mesh sides,(100% polyester), it fits all sheet style and all mattress depths from 6" to 22". Hypoallergenci material is great for asthma, eczema and allergy sufferes. Airflow membrane allows air to circulate through the pretector Twin XL size(39x80"),Peace of mind life time Warranty