Miele Filter SF-AH 50 Active Hepa,

Designed to create a comfortable environment for people who suffer from pet allergies and dust pollen. The filter retains 99.999% of all particles* leaving your room and the ambient air hygienically clean (*according to EN 1822:2011) Now with innovative Timestrip® indicating when the filter needs to be replaced. Suitable S4000, S5000 & S6000 series.
TimeStrip®
This filter has been designed with an indicator ‘TimeStrip®’ set to prompt you a year after it has been activated. This is when we advise that you look to change your filter in order to ensure that your vacuum cleaner is working at its optimum performance.
To activate the TimeStrip®, press on the green arrow to the left of the strip when the new filter is fitted. Thereafter, a red fluid starts to creep from left to right of the strip over a period of approx. one year. Once the fluid has reached the far end of the strip and the bar has changed completely to red, the word ‘Replace’ will appear, indicating that a new filter should be fitted.