6004ZZ (ID = 20mm, OD = 42mm, Thickness = 12mm) 6004-2Z bearings are shielded on BOTH SIDES to retain lubricant Made of carbon steel, durability and resistance to deformation under heavy loads ABEC 1 (P0) tolerance, Z2 noise level for most general uses 5050 static load newtons and dynamic load of 9400 newtons