AST 5100 Series Coilovers Honda Civic EJ2 (94-95) Non Inverted (ACS-H1003S) w/HWThe 5100 Series shock absorbers for the 1994 1995 Honda Civic Si 1. 5 (EJ2) utilize non inverted high performance monotube technology. In the past, these were known as the 4100 series. Monotube design shocks absorbers give your car a better performance than the standard twin tube design, the gas pressure is separated by a floating piston, and eliminates cavitation and airation within the oil chamber. The 5100 Series shocks allow rebound adjustment