The one piece of gear you will never sell

It's not that it's great, but I've got a 40-year-old Stanton gyropoise turntable in my studio system.  I seldom use it and it has a fairly fresh stylus (you cannot replace the cartridge in it!) so it's probably going to remain here as long as I do.  FWIW I have another, better TT in my main system.

My Stax 009 headphones!

For me the one piece of gear that I will never sell is my restored Accuphase E202 integrated. The reason being is that to me it has it all should I ever be forced to sell my other gear. Enough power to make lots of speakers sing. It has a good phono stage and headphone output to.

I'll go with my amp, Deja Vu Audio amp, a push-pull EL34 amp putting out 17 watts per side. I love this amp especially since the Aerovox cap upgrade I did last year. It's reliable, sounds fantastic, and is cheap to retube just 4 EL34's 3 6sn7's and a rectifier tube. The same 3 6sn7's have been in there for about 5 years. Power tubes right now are Psvane but I also use Gold Lion KT-77's. A classic and a keeper.

I dream of one day having THE system where nothing needs replacing, but I suspect that really IS a dream. That said, I own a SMcAudio VRE-1 preamp that I consider the finest piece of equipment in my rig, and certainly the preamp I will likely keep for the rest of my days. I've some gear that I have owned longer (a Naim Nait II still sees some use but I am neither wed to it or motivated to sell it, which is not the same as wanting to keep it forever). The VRE-1 though, is just special and I long to feel the same way about other components in my rig.