The POSI/VRDI holders are reduced diameter insert holders designed to bolt between and fit within the bolt circle of standard ANSI pipe flanges. Standard materials of construction are 316 Stainless Steel and carbon steel. Precision knife blades are welded in the inlet of the holder.
The POSI holder is the primary holder for the POSIPRO rupture disc.
The VRDI holder is the primary holder for the VAPRO rupture disc.