3/8" x 3/8", lead free, brass barb pex coupling, for use with pex tubing & connected with stainless steel cinch clamps & cinch tool true value #608-743, astm f-876, astm f-877 to sdr-9 dimensional standards, nsf 14 & 61 for use in potable water systems, csa b137.5 standards, nsf cal-r certified for use in hot water systems where chlorinated 140 degree fahrenheit, hot water can be constantly re-circulated, wetted surface of this product contacted by consumable water contains less than 1/4 of 1 percent of lead by weight, meets ab1953 california & vt s152 vermont low lead restrictions.