Hi, there are new glasses for belay available. 18 piece. 14 if yo buy a pack of 10 http://es.aliexpress.com/store/product/Belay-Glasses-for-Climbing-LePirate-Light-Technical-Belaying-specs-Tested-by-proffesionals/1020501_32358135034.html They are the best I've tried from china.
Cheaper belay glasses