I do a very high volume of reverse grip and close grip bench pressing
Then 2-4x a week, I'll do either skullcrushers with dumbbells or pushdowns with the bent bar that looks like a V. I try to do them as brotastic as possible, pausing at both parts of the movement.
It's hard to find an exercise that I really feel the burn in the triceps though. The reverse grip benching does it especially on Wednesday when I do a pyramid. For triceps isolations it's hard to find the right rep range as well. I've settled with picking a lightish weight and doing them rest-paused for 5 sets. So a set of 10, 15 breaths, set of 10, 15 breaths for 5 rounds.
If I go high reps, the weight is too light to feel it. Too heavy is no good either and it's hard to rack up decent volume with sets of 15 so I find these rest pauses ideal