4×105

4x105 refers to a specific battery configuration consisting of four D-cell batteries connected in series, each with a nominal voltage of 1.5 volts. This arrangement results in a total nominal voltage of 6 volts (4 batteries × 1.5 volts/battery = 6 volts). The "x" symbol denotes a series connection. The "4" indicates the number of cells, and "105" likely refers to the battery size, which is D-cell. D-cells are a standard size of dry cell battery, larger than AA or AAA cells, and are often used in devices requiring higher power or longer runtimes.

This 6-volt configuration is commonly found in various electronic devices. Examples include portable radios, flashlights, and some toys. The higher voltage compared to typical 1.5-volt or 3-volt battery packs allows for more power delivery to the device's components. The series connection ensures that the voltage of each battery adds up, while the current capacity is generally limited by the lowest capacity cell in the series. This configuration is chosen when a stable 6-volt power source is required and the physical size of four D-cells is acceptable.