All credit goes to the original author Helios467: https://mods.factorio.com/mod/promethium-belts

Why this mod rebalance ?

I like the idea of a new belt tier for postgame, but I find the ones from the original mod too powerful (75i/s are better in my opinion).

The usefulness of this new tier allows you to scale up the factory once the game has been won and go for a megabase.
At this point, the cost of new materials should be higher to maintain a sense of progress.

I also added modded science packs to the research cost (should work)

Features

75 items per second (+15)
13 tile underground belt connection (+2)
Constructed in foundries
Constructed only on Vulcanus
Consumes twice as much heat on Aquilo

Research

Unlocked after promethium science packs and turbo transport belts have been researched
Crafted with 5k x 60s of every science pack excluding military (This include modded science packs)

Promethium transport belts

1 x Turbo transport belt
1 x Holmium plate
2 x Promethium asteroid chunk
100 x Lubricant

Promethium underground belt (x2)

2 x Turbo underground belt
4 x Holmium plate
16 x Promethium asteroid chunk
400 x Lubricant

Promethium splitter

1 x Turbo splitter
2 x Holmium plate
1 x Quantum processor
6 x Promethium asteroid chunk
300 x Lubricant