In contrast to the most common testers, the XT1 can reliably test almost all types of batteries and rechargeable batteries. It measures battery voltage in volts, percentage capacity, and internal resistance, which is usually reserved for very expensive measuring devices in the industrial sector. The device has a current mode and features a power-saving mode. Supplied with two contact pins, it is intended for use only in protected indoor areas and away from sunlight. It requires 2x AAA batteries (do not use rechargeable batteries, only 1.5 V alkaline batteries), which are not included.