extra-specific interaction

Different stores have different prices; as do different regions. It is not possible to know a specific price from a specific restaurant.

Sorry if my answer isn't specific

But I believe it is called a leap-year

There is no third region. However, there are extra places you can visit by completing specific task,

Wireless headphones can range in all sizes from extra small to extra large, the same as any normal headphones. Check with the manufacturer of the specific headphone before purchasing.