Specification:Model: NK12/12Inner and Outer Ring Material: Chromium Steel (GCr15)Cage Material: ST13 SteelNeedle Roller Material: Chromium Steel (GCr15)Bore Diameter (d): 12mmOutside Diameter (D): 19mmWidth (B): 12mmStatic Load Capacity (Cor): 6400NDynamic Load Capacity (Cr): 6050NMaximum Rotational Speed (Oil): 25000rpm Package Content:5 x Needle Roller Bearing Description:-Needle Roller Bearings with Machined Rings are bearings with high load carrying capacity and stiffness.-These bearings are especially suitable for high dynamic loads or radial-limited installation.-Assembling inner and outer rings separately permits interference fits for shaft and housing.-For various applications such as agricultural and construction equipment, pumps and compressors, and two-cycle engines, among others.-NOTE: Install with press machine or special tools instead of hammers because beating may lead to local deformation.