Review on Uxcell A13070900Ux1050 Waterproof Connector Diameter by Deejay Devarashetty

They seem to be quite well made. I pulled it all the way down and measured the hole. It reaches a size of 3.25 mm. I couldn't get the 3.4mm wire to actually hold without slipping. Anything close to 4mm or more seems to work well. I wish it had come with an o-ring to seal it in the unthreaded hole. Overall this is a decent product and I will buy them again.