Feature●All Radnor fittings are manufactured to CGA-standards●In addition to CGA-numbers, many popular fittings commonly are refered to as A-size, B-size, C-size and D-size.●These letter designations are included in the product●Package:25/EADescription All Radnor fittings are manufactured to CGA standards. In addition to CGA numbers, many popular fittings commonly are refered to as A-size, B-size, C-size and D-size. These letter designations are included in the product discriptions.