Our ZDV Union Assembly is Valco Compatible and precision machined from 316 stainless steel. Our mechanically strong and reliable union offers zero dead volume (ZDV) allowing tubing to butt up against each other without interrupting the fluidic path. It is designed for 1/16″OD tubing and has a 10-32 Coned thread port configuration. It comes with (2) U-320/U-321 stainless steel fittings.