The ProPress copper press fitting system from Viega provides quick, easy and reliable connections for wet and dry fire sprinkler systems. The fitting is UL listed for Type K, L and M copper tubing and with NFPA 13, 13D and 13R sprinkler systems. The ProPress system joins copper tubing in just seconds, does not require flame or flammable gases, and can be used in commercial, industrial and residential applications. More than 200 fittings in sizes from (1/2") 3/4" to 4" are available. Viega.