Prefilter for LR5300 air purifier, coarse dust filter class G4 (EN 779) , separation efficiency 85 - 98%. Supplied = assembled. Product type = accessories. Z-line coarse dust filter as a prefilter for the main filter. For specific coarse dust particles up to 3 m. Separation efficiency 85 - 98% for 10 m particles and 30 - 55% for 1 m particles. Note: regardless of the filter cartridge indicator, the filter must be replaced after any work with pollutants. If the composition of the filtered particles is unknown, then the complete filter should be replaced after use on the respective construction site. Both filters must be replaced to ensure the dust (contaminants) cannot be introduced into clean areas.