COMPATIBILITY: The heat moisture exchanger is compatible with Z1, Z2, and other CPAP machines. The filter connects between the hose and tubing. To confirm compatibility, compare the diameter of the filter’s inlet/outlet with that of your machine’s tubing. PORTABLE DESIGN: The heat moisture exchanger features a thick translucent housing and a blue sponge filter. The translucent housing allows visual confirmation of proper installation. The blue sponge filter captures airborne particles and helps retain heat and moisture from exhaled air. HIGHER PERFORMANCE: This waterless humidification unit requires no power source and occupies minimal space. The high-density sponge absorbs heat and moisture from exhaled air and ambient environment. EASY TO USE: Install the heat moisture exchanger between the CPAP machine and mask tubing. A hose is required to connect to the mask. Once installed, turn on the device to receive continuously humidified airflow. Note: This heat moisture exchanger is not compatible with masks featuring a short interface. REPLACEMENT TIME: Replace the heat moisture exchanger after 7 days of use for optimal performance. Actual lifespan may vary depending on environmental conditions. Color: Transparent & Blue Material: Plastic Package Contents: 10 x Heat Moisture Exchangers Note: Light reflection and display settings may cause slight color variation between the image and the actual product. Measurement tolerance: ±1–3 cm.