The nozzle is made from brass and can be soldered to a copper tube using plumbers solder. Remember that the diameter of copper tubing is based on the ID so a 1/2” sweat fit nozzle will fit a thick wall 3/8” copper tube, etc. Annealed copper tubing tends to be coiled and has to be straightened before inserting into the nozzle for soldering, Straight copper tubing tends to be hardened and does not bend easily, unless you flame anneal it. The 3/8" Flat nozzle has a width of 0.380" and an aperture of 0.050". The 1/2" Flat nozzle has a width of 0.510" and an aperture of 0.050".