SRJQXH 3 Pcs 6mm Pneumatic Connectors, Pneumatic Bulkhead Fitting, Quick Connector Connectable Pipe Diameter, Can be Used as Fixed and Connecting Trachea : Amazon.co.uk: Business, Industry & Science
RS PRO Bulkhead Tube-to-Tube Adaptor, Push In 8 mm to Push In 8 mm, Tube-to-Tube Connection Style | RS