Variable Autotransformers (Commonly known as Variacs) are great devices for protecting your prized pieces of vintage audio equipment from unnecessary stress due to elevated modern mains voltages.

Back in the day, 117VAC mains were the standard. In modern times, voltages range from 120VAC to over 127VAC depending on time of day and your location in the country. 

When feeding a vintage piece of equipment designed for 117VAC from a regular outlet in your home, the elevated mains can raise heater voltages for vacuum tubes as well as almost all power supply voltages. This causes unnecessary wear and tear on tubes and other electronic components.

Using a Variac to back the voltage down to acceptable design levels helps prolong the life of your vacuum tubes and may extend the routine maintenance interval.

This Staco L221 is rated at 1.75A which makes it acceptable for use with most tube and solid preamplifiers and sources.

This device should not be used with power amplifiers.

The scale printed on the front of the unit is 0 - 130% and does not indicate output voltage. A digital multimeter on the AC Setting should be used to properly set the output level for your specific situation.

Item	Included
Original Box	Not Included
Manual	Not Applicable
Remote	Not Applicable
Cables	As Pictured
Physical Condition	7 / 10
Working Condition	10 / 10