Coil Spring.
COIL SPRING-REAR Coil Spring
Fits Impreza
Suspension Coil Spring
Your coil springs are not especially prone to failure, but if they have been cut, clamped, or heated to have the vehicle lowered, your Subaru might benefit from replacing the strut springs. Excessive rust can make the springs more prone to failure. Contact your local Subaru service department to have your suspension system evaluated.