Differnt focus for each eye?

All binoculars (except some really cheap rubbish) have a different focus for each eye. There are two types. Binoculars that have two individual eyepieces that turn and no center focus wheel. This is common to military, astronomy and binoculars used at sea.

The other is the usual center focus binoculars that have a wheel between the two barrels. They will also allow either the left or right eyepiece to turn to focus for one eye. The reason is that manufacturers take into account that each eye is slightly different.