I picked this piece up a few years ago and just found it hiding behind some other pieces... I am told that it is Turkish but am not sure. I've looked in the GIFONA book numerous times and am positive this is a CD 506, but I found only about 2 tiny threads on the top.... Not enough to hold it to a pin that's for sure. When I first got it I didn't inspect it that much and thought it was threadless! Does anyone know more information about it, or a possible value?