Variations of size is possible because each basket is handmade. Mattress:firm foam mattress that can fit the dimension of the basket is recommended. In addition, the baskets may have extra straws sticking out, please trim with scissors. Keep basket away from all heaters, fires/ flames or stoves. Fireplaces, campfires, open windows, water (running or standing), stairs, window blinds and any other hazards which can cause injury.This item is made of elephant grass.