This is a 625 mm front wheel that is intended for Dutch bicycles but can be fitted to any bicycle capable of fitting a 28" tire between its forks!
What's the difference between 700B wheels and the more commonly-seen 700C wheels? 700B rims are slightly smaller in diameter and much wider, allowing for larger tires to be used in the same space, making for a more comfortable ride with better handling. Some folks use them for touring, or even on gravel bikes!