This filter features DNA's advanced FCd (Full Contour design).Installation of the filter is very easy, simply follow the information that can be found in the BMW workshop manual.The filtering efficiency is extremely high at 98-99% filtering efficiency, with 4 layers of DNA® Cotton.The flow of this DNA Fcd filter is very high, 28.05% more than the BMW stock paper filter!DNA Fcd air filter flow: 204,50 CFM (Cubic feet per minute) @1,5"H2O corrected @ 25degrees Celsius.BMW stock paper filter: 159,70 CFM (Cubic feet per minute) @1,5"H2O corrected @ 25degrees Celsius.This DNA filter is designed as a High flow filter for road and off road use.Compatible with:BMW R45N 1978-1985R65 1978-1995R65 LS 1978-1984R80 GS 1980-1987R80 ST 1980-1986R80 1984-1985R80 RT 985-1995R100 CS 1976-1984R100 RS 1976-1975R 100 RT 1976-1995R100 S 1976-1984R100 T 1980-1984R100 T Sport 1980R100 GS 1987-1995R100 PD 1987-1995R100 MYS 1991-1995R100 R 1991-1995