VARTA Type 04120 / LR20 D battery
VARTA Type 04120 is a standard D battery in the LR20 size. It is a single-use battery with alkaline chemistry, making it suitable for applications where a stable 1.5 V supply is needed without the need to recharge or switch to a rechargeable solution.
In practice, it is a large cylindrical battery type typically used in equipment with space for the D format. This size allows for good capacity, which is why it is often chosen for devices that need to run for long periods at a time. The battery weighs 135.1 g, has a diameter of 34.2 mm, and a height of 61.5 mm.
The official IEC designation is LR20, and the nominal voltage is 1.5 V. The battery is based on Primary Alkaline Manganese, i.e., zinc/manganese dioxide. VARTA specifies a typical capacity of 16,500 mAh under high-ohmic load, and the shelf life is stated as 7 years when stored correctly.
This makes the battery relevant for professional operation where a known standard size and a stable spare part for equipment requiring D cells is needed. It is also a practical type when working with devices that are not permanently connected to a power source.