Locks FS 39B is a high quality sulphurised fatty mineral cutting oil specially blended to satisfy the needs of multi-spindle, multi-tool lathes for machining steel up to 45 tons tensile strength. The well-selected active sulphur additives provide excellent extreme pressure property to prevent localised welding between chips and the tools. It enhances tool life and surface finishing. This product is highly recommended for manufacturing stainless steel watch cases.