This is long-type 16mm inner diameter linear bearings in its pillow-block housing. This bearing is twice as long as the standard linear bearings , and actually contains 2 linear bearings side-by-side in each housing.
Perfect for those installations which would normally require 2 bearings butted together (e.g. Z-axis)!
Widely used in cnc, cutting machines, industrial, low noise and high speed electric motors, construction machinery, automotive components, pumps, and machinery.
Note: Open type slide block is suitable for supported shaft which is much more rigid as shown in the photo below