Very rare piece of equipment: a genuine Galeazzi Air Valve Holder. This is the first one I have ever been able to offer. Price €250,- plus shipping.
Photo of helmet is from the book 'Palombari della Marina Italiana'. This book can be ordered through this website: http://www.deepseaclassifieds.com/diving-books-int/book-int-palombari-della-marina-italiana.html
Brass Galeazzi Air Valve Holder.