I used to use the earlier version of this from Jaycar:
https://www.jaycar.com.au/portable-1...splay/p/MB3749
It's fine for just running a mount for the night at ~13AH. But forget it if you need to power more hungry things like dew heaters or cooled cameras as well. Can be charged by solar (built-in MPPT controller), 12v or 240V.
Mark.