White Lettering on solid black t-shirt. This is a cotton-polyester shirt that will shrink only slightly when washed

Please check with me about size availability. I only have XL and XXL sizes left.

This shirt is an off-shoot of an idea I had to produce a funny simple diagram for display vacuum tub fans. The magic eye vacuum tube (valve) displays a green glow for use as an indicator in old vacuum tube devices like radios and stereo equipment. The joke/double meaning of this saying on the t-shirt is rather obvious.

If you like glowing tubes you can show your affinity to the magic glowing tubes with this shirt.