Under Malaysia's regulatory framework, IVD devices are classified into risk-based categories (A, B, C, and D) depending on the potential risk they pose to patients and users. B-class IVD devices are considered low-to-moderate risk. They are typically more complex than A-class (lowest risk) devices but present fewer risks than higher classes like C and D. Examples of B-class IVD devices may include certain reagents, calibrators, and control materials used in medical laboratories for diagnostic testing.