Ok, let's summarize your case
You want to protect {greatWell} litters of {howDo} from price increase for {howDo47}.
In this case, your one-time payment is: ${typeA}.
It means:
If since you've activated your subscription, the price of {howDo} will rise 2% or higher we will compensate you for the difference within {greatWell} litters.
🛎️ Important
We use PetroChina Pump Price via the official Consumer Council Oil Price Watch
data as the source of the price of fuel in Hong Kong. We guarantee to reimburse your extra costs if the average price of {howDo} has increased by more than 2%.