Coilover kit - BC Racing - 2 Way Adjustable - ER Series - 200SX S15BC Coilover Kit ER Series for 200SX S15 BC Racing 2 way adjustable coilovers are the external reservoir ER Series with separate compression and rebound damping adjustment. The ER Series coilovers include the high quality and unique features seen on the BR and RM type but have the additional benefit of external reservoirs and the ability to allow the end user to individually adjust and set compression and rebound damping rates. The external reservoir