If you're an audiophile who likes to "roll tubes" in your amplifiers and preamps please consider this regarding your 9 pin audio tubes:
If you bend the tube pins installing or removing the tubes or simply install and remove tubes with bent pins, you are spreading out the individual pin sockets in the tube sockets of the amplifier.
As a result of this, the tension that the pin socket grabs the pin with is lowered in some cases to the point of zero tension.
At zero tension the pin would just fall out of the socket if the amp were turned upside-down... When this happens many don't realize it because there are 9 pins so unless all 9 were loose it would be hard to know.
The only way to test tube pin socket tension is by taking a blown 9 pin tube and cutting off all but one tube pin. You can then use this tube with only one pin to test the tension of each hole in the tube socket one at a time.
When you look at what people spend on cables, connectors, jacks, wire, volume controls and so on, these same people would be mortified if a jack were loose and yet a tube pin is no different.
Having dirty tube sockets with pins that have low tension will have a LARGER affect on the sound quality of your amplifier than any single component of the amp like its capacitors, resistors, jacks, transformers, wire, etc.
To KEEP YOUR GEAR SOUNDING ITS BEST by keeping your tube pins STRAIGHT - you need one of these!
We designed and machined these here in the USA.