The institution of knights was already well-established by the 10th century. While the knight was essentially a title denoting a military office, the term could also be used for positions of higher nobility such as landholders. The higher nobles grant the vassals their portions of land (fiefs) in return for their loyalty, protection, and service. The nobles also provided their knights with necessities, such as lodging, food, armour, weapons, horses, and money. The knight generally held his lands by military tenure which was measured through military service that usually lasted 40 days a year. The military service was the "quid pro quo" for each knight's fief. Vassals and lords could maintain any number of knights, although knights with more military experience were those most sought after. Thus, all petty nobles intending to become prosperous knights needed a great deal of military experience. A knight fighting under another's banner was called a "knight bachelor" while a knight fighting under his own banner was a "knight banneret".