Best Adapter Tube Nuts

M6 metric round coupling connector nuts, 10mm outside diameter, 25mm height.All connectors are fully threaded internally.Connectors are used to connect two threaded parts together. Thread size: M6/0.24"; product Name: round connector nuts.
Reviews
Find Best Price at Amazon"These are high-quality cylindrical nuts that are fully threaded internally."
"the holes are not centered in the studs."
"Works well for intended purpose."

M8 metric round coupling connector nuts, 12mm outside diameter, 25mm height.All connectors are fully threaded internally.Connectors are used to connect two threaded parts together.Ideal for welding into tubes to manufacture 4 link bars, ladder bars, wishbones, Castor arms, compression struts, watts linkages etc.Save time by using these in place of drilling and tapping out solid steel. Thread size: M8/0.3"; product Name: round connector nuts.
Reviews
Find Best Price at Amazon"unique find, perfect for my application."

M6 metric round coupling connector nuts, 10mm outside diameter, 20mm height.All connectors are fully threaded internally.Connectors are used to connect two threaded parts together. Thread size: M6/0.24"; product Name: round connector nuts.
Reviews
Find Best Price at Amazon"They fit on my Jeep doors."
Best Flared Tube Nuts

Size: 5/16". Enter your model number to make sure this fits.
Reviews
Find Best Price at Amazon"Excellent product but pay attention to the description and not so much the picture."
Best Union Tube Nuts

This Legris 0110 nut compression tube fitting is made of brass, connects to a metric tube, and is suitable for high-temperature, pressure, and vacuum applications. It is made of brass for corrosion resistance, ductility at high temperatures, and low magnetic permeability, and has an operating pressure rating range of 200 to 500 pounds per square inch (psi) at a temperature range of -65 to +250 degrees F. This nut compression tube fitting meets the Restriction of Hazardous Substances Directive (RoHS), adopted by the European Union (EU), and is suitable for use in high-temperature, pressure, and vacuum applications.
Reviews
Find Best Price at Amazon"5 stars what more to say."