Rubber plugs offer an environmental and material protection system preventing oil and chemical spills and leakages. Multiple usage in applications such as any Hydraulic maintenance, heavy industry, offshore, forestry, construction, lifting, shipping, demolition, military, transportation, Automotive, Motorcycles and so on. The Original YELLOC rubber compound is silicone free and highly resistant to many chemicals, acids and other aggressive fluids. Temperature range -25°C to +90°C (-13 F to +194 F). All types are re-usable and used for NON-Pressurized systems. No tools needed.