Review on HHIP 3900 1187 Coupling Nut 2 13 by Jeremiah Whiteley

external hex closer to 1 3/8" across flats --- requires a 1 7/16" wrench but is a bit loose. This measurement was critical in my application, but probably not for most. I also bought a Morton EN-4 which is a true 1 7/16 inch (minus a hairline for spacing) and is rounded to the hex corners rather than these. The Morton piece is definitely of a higher quality (i.e. aerospace). Article, but in 99% of applications hardly worth 5 times as much. Although the images look quite silvery as raw or galvanised, it's just a light trick as it really is a black oxide as described.