(!!) (#3 12AT7 Value Pair) ECC81=12AT7 Mullard NOS old logo made in Hyperlec Brive France in white boxes 1970's
1 low noise pair) ECC81=12AT7 Mullard NOS old logo made in Hyperlec Brive France in white boxes 1970's (good in guitar amps and a "best value" 12AT7)
1 tube) 7.0/7.6ma Gm=4600/5000
1 tube) 7.4/7.4ma Gm=4500/4500
Matched on Amplitrex
Mullard clone made in France
Hyperlec (later known as T.R.T and R.T.C.) was an electronics factory in Brive (a.k.a. Brive la Gaillarde), which is a town in the Corrèze region of France.