Certain mattress material (4)
I believe the answer is:
foam
(Other definitions for foam that I've seen before include "Sea froth" , "Bubbles on liquid" , "Froth created by wave or soap" , "Fizz, froth" , "Mass of small bubbles" .)
I believe the answer is:
foam
(Other definitions for foam that I've seen before include "Sea froth" , "Bubbles on liquid" , "Froth created by wave or soap" , "Fizz, froth" , "Mass of small bubbles" .)