This resin exhaust set from SBS Model features 1/72 Spitfire exhaust (round) late types: Mk. 21, 22, 24, 45, 46, 47 for Special Hobby kit.  This set contains 2 parts.  The exhaust pipes are hollow on the end for added realism.

You can purchase these and other fine resin detail items directly from SBS Model or from the many retailers that carry their products.  

Steve Bamford