What, in your system, have you owned the longest?


For me, it's my Zerostat. Bought it in the '80s- most likely 1986 or 1987. 
zavato
We moved 10 yr ago, and I started over as far as most of the gear goes.

What I've owned the longest are some acoustic treatments (15 yr) and two JL Audio f112 subs (13 yr). Next is the equipment rack (9 yr), and after that the speakers (6 yr).
I have Acoustat Spectra 33 electrostatic speakers.  I bought them new in 1988. 
I was going to say the speakers, but the reality is the Furman 15 A elite something something is definitely what has lasted the longest.