Hi Vagelis - I’m using a Turnigy “5.0, 20-30C” with good results. It’s a tight fit - one has to slightly angle it in to clear the foam padding on the rear sides of the compartment. (Obviously, it’s a 3S pack) GL & keep that Iris+ up!
The battery fits in the Iris+ without any modification beyond the need to shorten the power lead (note the battery dimensions). This one comes with the Deans (T-plug) attached, but it also includes an XT-60 plug for you to solder on. Yes there is the same battery with the XT-60 plug already attached, however, since this battery was not made specifically for the Iris, the power plug lead is very long and almost impossible to cram into the case…so you’ll need to solder, hence the suggestion to get the one that comes with the new connector.
I hope this helps some of you out as finding suitable batteries has been a challenge. I certainly will be ordering more of them.
Cheers,