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Can you add some more description to your issue? There are lots of turrets with their own infinite research list. There may also be some weird mod interactions happening.

No it's my bad, I just checked again and saw that the tesla turret is under "laser" category.

While I have your attention - would it be possible to add tower HP research? Towers are quite squishy late game.

It's sadly not possible. The Factorio API doesn't support that. I'd have to make new versions of the turrets with extra HP. Their health stats are based on vanilla turrets so it should be close to other types. Some turrets are much sturdier than the Tesla turret. It's an early game turret and balanced as such.

I recommend adding combat mechanics overhaul and turning on the "walls block spitters" option and maybe turning off the extra enemy health. I try really hard to balance this against vanilla so adding 50% extra health to biters can throw a wrench in things.