The Dermacea™ I.V. Drain Sponge is made of a synthetic blend of rayon and polyester that helps provide fast wicking action and superior absorbency. The unique pre-cut T-slit conforms snugly around drains, catheters, chest tubes, I.V.'s and tracheotomies. 4" x 4" (10.2 cm x 10.2 cm).