Service parts pricing is like buying toys from a toy store. You know how some toys come with small parts that you might lose or break? Those small parts are called service parts.
Service parts pricing is how much it costs to buy those small parts separately if you lose or break them. Just like how some toys might cost more if they come with more accessories, some service parts might cost more if they are more important or harder to make.
For example, if you bought a toy car that came with a spare tire, but then you lost the spare tire, you might have to buy another one from the toy store. The toy store would look up the service parts pricing for the spare tire, and then charge you that price to buy the new one.
Overall, service parts pricing is just a way for companies to make sure they can keep making money if you need to buy small parts separately for something you already bought.