A plumbing assembly includes a plumbing fitting having a body. The body includes a main body portion having a main bore extending there through. A peripheral body portion extends from the main body portion. The peripheral body portion includes a distal end and a sampling bore extends through the peripheral body such that the sampling bore is in fluid communication with the main bore. The plumbing assembly further includes a sampling valve threadably coupled to the distal end of the peripheral body portion of the plumbing fitting. The sampling valve extends at least partially into the sampling bore without extending into the main bore. As such, the main bore is unimpeded by the sampling valve and use of the sampling valve imparts substantially no pressure drop in a fluid passing through the main bore of the plumbing fitting.