Support bearing which comprises a first ring and a second ring disposed inside the first ring and substantially coaxial thereto. The first ring and the second ring define between them an annular hollow space in which a cage structure is disposed comprising two circular crowns disposed distanced from each other and between which a plurality of rolling elements are disposed, provided to allow the reciprocal rotation of the first ring and the second ring. The bearing is suitable to support a roll which is used particularly, but not exclusively, in coating processes of a metal product, such as for example strip, wire, bars, by means of metal coating methods such as those known such as galvanization, aluminizing or other similar coating processes.