55 mm x 120 mm x 29 mm 55 mm x 120 mm x 29 mm timken 6311-NR Deep Groove Ball Bearings (6000, 6200, 6300, 6400)

YOU’LL Alloy Steel ball material: FIND AN EXTENSIVE SELECTION NTN BEARING MANUFACTURING DE MEXICO,S.A.DE C.V. 55 mm x 120 mm x 29 mm OF 55 mm x 120 mm x 29 mm 55 mm x 120 mm x 29 mm timken 6311-NR Deep Groove Ball Bearings (6000, 6200, 6300, 6400) FOR SALE.

What is 6311-NR bearing cross reference？