Reinforced design for longer life and better efficiency than standard wicking filters. Removes minerals from water. Anti-bacterial treated. Fits Bemis models 4000 and 6000 series. Metal reinforcement. Adds rigidity to shape of the wick filter when moistened. Also adds stability with today softer, more absorbent paper. Prevents slumping or insagging in over time or when wet. Helps maintain the humidifier designed output. Wick filter fits 400, 4D7, 600, 4000, 6000, ED11 series console (1041).