Stainless Steel Pigtail for Nitrous Oxide The Amico stainless steel pigtails shall have a core which consists of teflon (polytetrafluoroethylene) with two outer reinforcing jackets of stainless steel braid. The braid will incorporate a type 304 full hard drawn stainless steel wire. It shall consist of a 1/4” nominal I.D. The Amico stainless steel pigtails shall come with a check valve equipped to one of the ends. Note: Burst pressure ratings for pigtails are determined at room temperature with the hose in a straight line. A safety factor of 4:1 or 5:1 should be used for normal applications. Impulse and shock pressure applications may require a higher safety factor. Note: Do not apply heat to pigtails. All cylinder connections machined to CGA specifications for applicable gases.