The Energy Suspension Hyper-Flex rear coil spring isolators for 2000–2004 Ford Focus are polyurethane isolators intended to replace factory units and assemble to the chassis the same way as OEM parts. Made of Hyper-Flex material, they are claimed to last several times longer than rubber, maintain factory ride characteristics, and offer a simple way to preserve ride comfort while improving longevity of the isolators.
Energy Suspension 00-04 Ford Focus Black Rear Coil Spring Isolators