Grave Digger Moose Cow in Heat's scent stays strong regardless of weather conditions and is specifically designed to resist moisture and freezing. This powerful combination is packaged in a heavy-duty bag that locks in freshness with an airtight seal and is lightweight and easy to carry. Once opened, the TRS (Time Released Scent) attracts rutting bulls from great distances, zeroing them in on the scent of a moose cow in heat. Grave Digger lasts up to 30 days, eliminating the need to re-visit rut pits or feeding sites thus preventing contamination by human odor.