Review on Circuit Performance Black Bolt Valve by Rick Malloy

I would have given more for it but mine arrived on a Sunday - the day before I had scheduled an appointment to have my tires fitted; it was urgent as I had a slow tire leak that was accelerating and only lasting a day or two between inflations; and one of the jam nuts was split in half rendering the whole set unusable. Also, I would have had to wait TWO DAYS for delivery to get a replacement kit as it was the fastest option available.