Geoff was right first time, it is a shade ring holder. For those of us with large hands/fingers it is not possible to reach within narrow shades to remove the lock ring so that the shades can be removed. The lamp is removed, and either of the 2 tools locked onto the ring, this is then unscrewed and removed. Simple really, but I have never seen any others. Obviously now that Geoff has had a second guess, his first guess is now not admissible, so there are no winners hey ho!
[This message has been edited by TrimixLeccy (edited 02-26-2007).]