Type A specified range is most commonly found on Japanese manufactured radiators.
Type A adapter is designed to work on radiator necks ranging from 15.75mm – 20 mm and can also be found on some late model water-cooled American V-Twins.
Type B specified range is most common on European manufactured radiators.
Type B adapter is designed to work on radiator necks ranging from 20mm – 24.5mm.
Adapter only; for use with Motion Pro Cooling System Tester (sold separately).