Genius battery chargers are fully-interactive and designed for safety. Many of the features include: auto-memory, the charger returns to the last selected mode when restarted; HF/HE switch mode design is high-frequency and high-efficiency for a light-weight, compact charger; rapid-charging technology charges batteries two-times faster than traditional linear battery chargers; multiple battery chemistry safely charges WE, GEL, MF and AGM batteries; variable input compensation gives 100% full charge even with varying A/C input voltages; extendable connectors have plug-n-play connections for easy accessory changes; and abnormality protection automatically shuts off if the charger remains in bulk charge mode for an extended period of time.