These springs attach to the manifolds of many Lambretta and Vespa exhaust systems.  The connection from the downpipe to the body is also normally completed with springs.  The spring can be turned as it has swivels both ends, it is easy to fit and cushions very well.  The annoying noise that is sometimes confused for cylinder pinking, is cancelled out due to the rubber sleeve.
 
Please check these are the correct length before ordering.