Sub-Micron Oil Removal Filters guarantee technically oil and particle free air. With Borosilicate Glassfibre filter cartridges, residual oil content of less than 0.01 (or 0.1, 1, 2) mg/M3 in outlet and particle removal of 0.01(or 0.1, 1, 5) micron are offered. Silicone treated borosilicate glass fibre media cartridge with in built pre-filter and final filter layers. Reticulated foam layer for oil drainage tested to ASTM D2986:91. Poly Butylene Terphthalate (PBT) end caps.