DDNV0001 1" No Lead Copper Union Fitting with Sweat to Male Threaded Connects

Purchased four of these for a water softener installation. The heavy duty construction gave me confidence these would seal properly. They were fairly easy to solder 1" copper piping to. On the threaded side, I used teflon tape with a little bit of Oatey pipe dope for connection to the whole house filter and 1" corrugated stainless steel tubing. Absolutely no leaks. Would highly recommend for any 1" piping job!

There are a number of responses about getting these to seal, and I've experienced the same thing. This type of metal-to-metal seal requires the sealing surfaces to be just about perfect. The inverted-bevel on the brass-side is usually fine, but if there is any imperfection (nick or scratch) on the copper side it could easily leak. Before trying the following, make sure there the imperfection (if it has anything) isn't TOO big - Just send it back if so. If you see or feel anything MINOR, here's what I did to ensure no leaks on mine: Take 1000-3000 grit sand paper and _carefully_ sand out any imperfections - Try to do this as evenly as possible. Don't try to reshape it, the goal is to make it super smooth. I followed that up with super fine Crocus cloth, which can polish to almost a mirror finish. Prior to assembly, put a light film of plumbers silicone grease on the bevel, copper ring, AND on the threads. Then get the two biggest wrenches you have (I used two 15" crecent-type wrenches, 18" would probably be better) and REALLY crank the nut down. If you're a "smaller" guy (or gal), crank it down as hard as you can.TLDR Summary:1. Send back if defects on sealing surfaces (copper especially) are too large.2. Polish the copper side; Sand paper and polish with super fine crocus cloth.3. Use light film of plumbers silicone grease on sealing surface AND threads.4. Don't be afraid to crank this down using a lot of force.4-of-5 Stars because of the additional work needed to get a reliable seal. YMMV

These worked better than the ones you find at the big hardware stores haven’t had a issue with them. Excellent product.

Really solid copper union. Fitment was perfect on both the sweat side for 1" copper pipe and the threaded side, as well as the union. Threads are machined well and fit together perfectly.No leaks at all after installation - BUT because the threads are so big, I couldn't put enough teflon tape in place to seal it properly and I had a few drips. I removed the teflon tape and went with PTFE paste instead and now everything is 100% bone dry!

The fittings I received (April 2023) are made in South Korea. The fittings are obviously made precisely, they don't use ferrules or rubber seal.

I needed to couple a 1" copper pipe to a water pump having a 1" threaded inlet. This union did the trick. I did not have the leakage problem reported by some in earlier reviews. Alignment of the two union halves is critical. One thing to be concerned about is that the mating union surfaces are not flat, as are many unions using an O-ring seal. The seal is metal on metal and requires at least 1/4" of play between the copper pipe and the device connected to the threaded half to enable the two union halves to be separated. As a result this union may not be suitable for use in closely confined spaces.

Thick copper, pretty well made. (Illustration showed the body being a little longer). I have no use for the copper to copper types, copper to bronze is the way to go.

Leaks no matter how tight I tighten. Very small amount but annoying