The present invention provides an adaptor that is suitable for attachment to an endoscopic device for delivery of a secondary gas. The adaptor generally comprises an adaptor body with first and second fluid transport components and can include a gas inlet on one of the fluid transport components suitable for attachment to a secondary gas source. A sealing member can be included to prevent leakage of any fluid (e.g., liquid or gas) that is transported through channels extending through the fluid transport components. The adaptor may be used in endoscopy methods and is particularly useful for adding a secondary gas source in an endoscopy procedure.