Review on Pack Of 3 Brass Compression Fitting Union For 7/8-Inch OD With LTWFITTING by Jason Wesley

These couplings are for 3/8 inch tube (actual OD 0.500). Not for 1/2 inch tube (actual OD 0.625 = 5/8 inch). It is really misleading to advertise 3/8 inch fittings as 1/2 inch fittings. Everyone is expecting the nominal size, not the actual size. As I write this review, there are plenty of complaints but no correction from the seller. None of the complaints actually explain the problem.Edit: I've learned a little more about this issue. It turns out that in some trades, 1/2 inch tube actually has a 0.500 OD and compression fittings refer to the actual OD. However, one of the most common uses of compression fittings is copper pipe for plumbing. Copper pipe has the ODs as mentioned in the first paragraph and you need 5/8 inch (0.625 inch) compression fittings. The vendor could have a lot fewer disgruntled, ex-customers if they would add "fits 3/8 inch nominal plumbing pipe" to the description.