According to the size and hook, the ceramic brackets can be classfied as following: Roth Ceramic Bracket0.022"/0.018"No Hook Item No: 1011-1Roth Ceramic Bracket0.022"/0.018"3#W/Hook Item No: 1011-2Roth Ceramic Bracket0.022"/0.018"3, 4, 5#W/Hook Item No: 1011-3Edgewise Ceramic Bracket0.022"/0.018"No Hook Item No: 1012-1Edgewise Ceramic Bracket0.022"/0.018"3#W/Hook Item No: 1012-2Edgewise Ceramic Bracket0.022"/0.018"3, 4, 5#W/Hook Item No: 1012-3 More Product Features Model NO.: 1011-1 Standard: 018/022 Company: Hangzhou Protect Medical Equipment Co. Ltd.