Electro-Harmonix' new, premium-grade 6V6EH tube is built to meet or surpass the USA JAN Phillips or hard-to-get RCA 6V6 tubes. If you have a vintage amp in need of new tubes, the 6V6EH is the one to withstand the higher plate voltages from the old amps' power supplies. The tube is tested to take up 475 volts with a higher grade of tri-alloy plate material and a tighter alignment of the grids. (info@ehx.com,www.ehx.com)