Compatible with Halo Bassinet, 18" x 30", Compatible with other,18”x30” Bassinets as well, Waterproof Replacement Mattress with Removable & Washable Mattress Cover BRAND NEW AND SELLING FOR HALF PRICE, $19! We purchase from Amazon for $37.99 back in June of 2023 and we never used it due to it not fitting our Graco bassinet. We didn’t realize this was meant for a Halo Bassinet. Premium Mattress Cover--Removable, Washable and Waterproof The ultra soft jacquard cover is removable and washable. It is also 100% waterproof to protect the foam from any leaks, ensures high quality sleep for your little one. Quality Zipper The quality of stitches will not popped and ripped.High quality zipper design reduce the risk of scratching which is friendly to baby's sensitive skin. Machine Washable Cover Wash before first use. Machine washable on gentle cycle. Tumble dry on low heat.