Every single active item, which have mini GUI [e.g jetpacks] on Bottom Left screen, is reducing my own FPS from 140-180 to 54-65 FPS. On my screenshots you can see my FPS with wearing jetpack and without jetpack. Also, if you gonna hiding your GUI by pressing F1, your FPS is gonna be stable until u return GUI back

Check this one:
Trins-mods/Gravisuit-Classic-Edition#26
Comment link: Trins-mods/Gravisuit-Classic-Edition#26 (comment)
Should have less impact on mc performance (I hope 👀)

Maybe it was a bad idea to check for IC2Classic's armor to display the info when writing the code for GraviSuit 🤔
I feel sorry about that.

@JohnnyAnakonda not IC2Classic issue.

@CrossVas thank you for solving this one for me.
Hope you are doing well.