The Wacker IRSEN-FU internal concrete vibrators feature an integrated inverter and an operating handle that is designed to reduce hand-arm vibration. With an integrated frequency inverter, the vibrators are designed to deliver stable, three-phase electricity to the motor when connected to a 120-volt, single-phase power source. The IRSEN-FU series includes the 38/115, weighing 26.5 pounds with a 1.5-inch head; the 45/115, weighing 28.7 pounds with a 1.8-inch head; and the 57/115, weighing 35.3 pounds with a 2.3-inch head.