This spring perch rubber isolator is a factory replacement part. The spring perch (required) is sold separately. Made by Subaru (FHI) so the fit, finish and quality are all excellent. Note that the actual strut tops are typically a maintenance item in the front and replacement should be considered whenever changing springs or struts because the strut top needs to be removed when changing struts or springs and the labor is considerable, so do it right the first time.