When sourcing brass fittings, the material composition is critical. You should prioritize CW617N or HPb59-1 brass for general applications, as these alloys offer excellent machinability and corrosion resistance. For potable water systems, ensure the fittings are Lead-Free (less than 0.25% lead content) to meet health safety regulations. Technically, the fittings must adhere to international threading standards such as ISO 228-1 (G thread), ANSI/ASME B1.20.1 (NPT), or BS 21 (BSPT) to ensure leak-proof compatibility with existing piping.