Batteries type D

D (R20) Battery

— perhaps the most large size used in consumer-grade batteries. Type D batteries (also known as R20, LR20, FR20, KR20, HR20) are cylindrical, about 63 mm long and about 34 mm in size. They are distinguished by high capacity and resistance to loads, but they do not fit well into compact cases, which is why they are used mainly in large and high power consumption devices (such as portable radios). But unlike rechargeable batteries, they are non chargeable.