That’s all the testing that was done. Seems to be real clean inside. Also the power cord coming out of the unit has the plastic coating of the outside part of the cord torn as you can see in the photos.

1400V PIV, 200mA DC current. We have hundreds of thousands of tubes for manufacturing purposes, all vintage american made. 2 If you are looking to re-tube and amplifier, guitar amplifier, preamplifier, compressor, equalizer, microphones or any tube equipment, send us the model number and we will take care of the rest, and generate a custom listing for you. 4 We carry most USA made brands such as RCA, GE (General Electric), Sylvania, Raytheon, TungSol and PentaLabs , just to name a few. 5 We also carry european brands such as Amperex, Mullard, Telefunken and Marconi , just to name a few but in less quantities.

1400V PIV, 200mA DC current. We have hundreds of thousands of tubes for manufacturing purposes, all vintage american made. 2 If you are looking to re-tube and amplifier, guitar amplifier, preamplifier, compressor, equalizer, microphones or any tube equipment, send us the model number and we will take care of the rest, and generate a custom listing for you. 4 We carry most USA made brands such as RCA, GE (General Electric), Sylvania, Raytheon, TungSol and PentaLabs , just to name a few. 5 We also carry european brands such as Amperex, Mullard, Telefunken and Marconi , just to name a few but in less quantities.

1400V PIV, 200mA DC current. We have hundreds of thousands of tubes for manufacturing purposes, all vintage american made. 2 If you are looking to re-tube and amplifier, guitar amplifier, preamplifier, compressor, equalizer, microphones or any tube equipment, send us the model number and we will take care of the rest, and generate a custom listing for you. 4 We carry most USA made brands such as RCA, GE (General Electric), Sylvania, Raytheon, TungSol and PentaLabs , just to name a few. 5 We also carry european brands such as Amperex, Mullard, Telefunken and Marconi , just to name a few but in less quantities.

RCA – Red Print. NOS – Strong TESTING. We have hundreds of thousands of tubes for manufacturing purposes, all vintage american made. 2 If you are looking to re-tube and amplifier, guitar amplifier, preamplifier, compressor, equalizer, microphones or any tube equipment, send us the model number and we will take care of the rest, and generate a custom listing for you. 4 We carry most USA made brands such as RCA, GE (General Electric), Sylvania, Raytheon, TungSol and PentaLabs , just to name a few. 5 We also carry european brands such as Amperex, Mullard, Telefunken and Marconi , just to name a few but in less quantities.