Internal Clutch Slave Cylinder (S0418) by RhinoPac®. With Bearing. Material: Aluminum. Tube Fitting Location: Base. Seal Type: O-Ring. Mount Type: Concentric. Thread Size or Retainer Type: Coupler. The concentric slave cylinder is mounted inside the bell housing, eliminating the need for the release fork and related hardware. The unique design provides precise release bearing travel with better alignment geometry. But since transmission removal is required for replacement you better use the best concentric slave cylinder available – RhinoPac.