Based on this product's specifications, here are some alternatives and similar models
Single-use battery Varta 4R25-2 19000mAh 6V
Summary description:
The Varta 4R25-2 is a high-capacity single-use battery with a 19000mAh capacity, designed for 6V applications. Utilizing Zinc Chloride technology, it offers reliable power for various devices. Its prismatic form factor and dimensions of 73 x 135.5 x 127 mm make it suitable for specific equipment needs. Ideal for long-lasting performance in demanding situations.