(!!) (Recommended Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (6.0/6.5ma and 6.1/6.8ma) 1-3% matched
(!!) (Recommended Pair) ECC40 Siemens NOS made by La Radiotechnique, Chartres/France 1967-1972 (6.1/6.4ma and 6.0/6.0ma)
(!!) (Recommended Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (5.8/6.6ma and 6.0/6.6ma)
ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1967-1970
(!!) (Recommended Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (5.5/5.6ma and 5.5/6.0ma)
