The wire backing is to support the filtration media. This further reduces the chance that the filter media could collapse. The use of stainless steel wire provides a strong, durable, AND low restriction way to provide the support.
The efficiency of a filter is described in terms of a percentage of particles caught at a certain particle size(and larger). Using the ISO 4548-12 multi-pass filtration efficiency test, Royal Purple filters are: -99% at 25 micron and larger -98.7% at 20 micron and larger -80% at 10 micron and larger
Vehicles under warranty should follow the vehicle manufacturer’s recommended change intervals. For non-warranty applications, the useful life of Royal Purple premium oil filters is the life of the engine oil. Vehicles driven in severe conditions should follow the change intervals recommended in their owner’s manual; severe conditions are defined as racing or commercial applications, frequent …
Royal Purple premium filters use 100% synthetic micro-glass media for superior particle removal with 99% filtration efficiency at 25 microns and larger, and 80% of particles 10 microns and larger.