Small Zero Dead Space Drain Valve Complete, Standard, 3/4" Beaded Pipe Side ArmSmall Zero Dead Space Drain Valve Complete, Standard, 3/4" Beaded Pipe Side Arm Features: Auto-Stop When Opening The Valve Anodized Aluminum Control Knob Is Laser Etched W/Directional Arrows For Opening & Closing The Valve Zero Dead Space Perfluoro O-Rings On Tip & PlungerZero Dead Space flush bottom valve is designed to prevent solids from collecting in the bottom of the vessel. The PTFE drain valve plunger is supplied with an Perfluoro and a TFE encapsulated o-ring for the tip and two Perfluoro o-rings installed on the shaft. The drain valve is connected to the reactor by a unique 2 beaded pipe valve seat that is sealed to the reactor bottom. Our valve permits total drainage of the vessel contents. The sidearm has a 1 beaded pipe fitting.