The Oeuf trundle mattress will give your overnight guests a comfortable night’s sleep on any of the Oeuf Trundle Beds. Fits the River, Sparrow or Perch Trundle beds. Made from lightweight but durable medium-density foam with a firmer base foam layer for added support. It’s non-allergenic and safe. The mattress is covered in quilted ORGANIC cotton fabric with a cloth binding. Made in the USA.