One replacement chamber for all Respironics REMstar M-Series R3 Heated Humidifiers.
This is the newest chamber design for the M-Series Humidifier that has a staggered inlet/outlet pipe arrangement with round rather than rectangular seals and improved latch and non-removable gasket. These changes were made to solve issues with water ingress into the machines that sometimes occurred with the original humidifier design.
*** Please note that these will not fit the R1/R2 M-Series Humidifiers ***
You can determine if you have an R3 humidifier by looking at the numbers below the setting dial. On the R3 humidifiers, there will be a white line under the number "5". See picture below: