Gas ring reducer

You either really need one of these and have been looking for one for ages - or not. Been struggling even to know what to call them haven't you? So the gas ring reducer is here at last so your espresso pot no longer teeters dangerously on your cooker threatening to spill the first coffee of the day all over you and the hob. Kind of look cool too. Like some dangerous frisbee. And just for a laugh I'm including a picture of my brother's.  WELL used. Looks like something you found on an architectural dig. 12.5cm across.