The ACUPWR AUD-300 step-up/step-down line-voltage transformer allows guitarists to safely use fixed-voltage amplifiers in overseas countries with different voltage standards. Hand-built in the U.S., it converts 220-240 volts to 110-120 (and vice-versa), uses thermal-protection circuitry, and will work 20 percent beyond its 300-watt capability. Other voltage combinations are available. Visit acupwr.com.