Cylinder tubes, rods, glands, pistons, end caps, and manifold blocks. Bore surface finish held in the range seals actually need, since too smooth stops the film forming and too rough abrades the lip.
Cross-drilled manifold intersections deburred and flushed, because a burr released into a closed hydraulic circuit reaches a servo valve within minutes. Sealing faces, port threads, and groove dimensions machined to spec.
