The 1 brass pipe is made of brass and copper. Brass and copper is good raw material for heater. Both brass and copper have good heat dispersion and heat-conducting property, especially copper. The nipple is brass made and pipe is copper made. The thread of brass nipple is 3/4 inch. The copper pipe is welded on the brass nipple, with a plastic protective cap. The brass nipple is made by CNC machining the brass hexogen bar. The copper pipe is made by custom extrusion.