High quality brass reducing nipple. Made in accordance with ISO R thread standard (BSP tapered male thread) and acid cleaned to ensure no swarf or contaminants. Used for reducing or stepping up thread sizes by using one nipple interface fitting.. Medium pressure ratings of around 35 BAR or 500 psi decreasing as sizes increase and depends upon media. All reducing nipple fittings are qualified according to certified ISO threa guages to ensure correct sealing, operation and life span.