guaranteed to be 100% compatible with any brand of pen.Bdesigned to fit any pen injector giving you complete peace of mind when using a BDIf your therapy is more complex such as a multi-pen Basal-Bolus regime, using BD which are compatible with all pen injectors, helps make life easier for you.compatibility means a brand for life.No matter whether your diabetes therapy or brand of drug changes, you can rely on BD to be compatible with all pen injectors.So whatever pen you use for diabetes care, you only need to carry a BD . Making life easier.BD Ultra-Fine+ the positive choice for people with diabetes.