1 EVAP Boot Adapter Per Order THE RULER IS JUST FOR VISUAL REFERENCE,NOT INCLUDED - HOW TO USE? How to make your smoke leak testing more easier while we are facing larger openings? Just fit the cone adapter into diagnostic site and inject your smoke through the adapter hose. THE MATERIALS: High quality silicone and brass,anti-corrosion. THE SIZE: Made for larger openings with a diameter up to 4.2 inches (107mm) and as small as 1 inch (26mm). We are original manufacturer from China,wholesale or OEM is acceptable,please feel free to let us know if you need any help.