NEST Fragrances Reed Diffuser-Hearth Reed Diffuser 175 mL / 5.9 Oz. NEST Fragrances Hearth Reed Diffuser has the aroma of a wintertime fire created by combining rich oud wood with frankincense and hints of smoky embers. Custom designed glass lightly touched with gold The alcohol-free formula releases fragrance slowly and evenly into the air for approximately 90 days.