Hi, I am after a bit of help if possible please, I have some old voltage regulators off of lorries and they use a 16025 , I can't seem to find them, assume they are obsolete, is there an equivalent? Photo attached.

Thanks in advance
Steve

 

Most of RCA transistors on general sale started 40xxx. I suspect it may be a "special", but it's just a bipolar transistor so isn't really that special.
If you can identify whether it is NPN or PNP, or whether it is a Darlington, then it should easily be possible to identify a replacement.
What is the spec of the regulator? Input voltage, output voltage, maximum current?
(My guess is that it will be a standard NPN bipolar transistor and that you could replace it by a 2N3055)