I have an ancient, and very expensive (at the time) "K06" crimper.
https://www.ebay.co.uk/itm/305044806299?chn=ps&_ul=GB&mkevt=1&mkcid=28
Bought it new about forty years ago. Non hydraulic and a lot larger.
A bit awkward to use because of its size, but it does not have all those small removable dies that could get lost or mixed up, or hydraulics which can leak slowly or fail.
Being an all in one piece tool, its the sort of thing you can just throw into the back of your truck and forget about it until you need to use it.
Then its all there and ready to go.
It works using compound levers exactly like large bolt cutters, and its just as powerful.
It has a pair of rotating turrets at the end that close against each other. Its a one piece tool without all the small parts that can get lost, and it does an excellent job of cable crimping from 6mm sq to 120mm sq.
It makes a hex crimp and stamps the size into the finished crimp, so it complies with work that requires formal official inspection.
If you get lucky, you might find one really cheap at a flea market or an auction, well worth grabbing.