... tees the most common. Stainless steel crosses, also known as four-way fittings, cross branch lines. A stainless steel cross has ... as temperatures change, because they are at the center of four connection points. A stainless steel tee is steadier than a ... cross; it behaves like a three-legged stool, and a stainless cross behaves like a four-legged stool. Stainless steel crosses are common ...