Transcend Micro 510 CPAP Resupply PackThe Resupply Pack contains a WhisperSoft Muffler Kit, a 4' AirFlex Hose, two PureFresh Filters, and an AirMist HME 4 Pack with adapter. These are the parts that see the most wear on a Transcend Micro 510 and the ones that affect sleep quality most directly when they're past their prime. Filters and the muffler should be swapped every three months. The AirFlex hose is short enough to pack anywhere and flexible enough that it doesn't pull or kink during