Vacuum Fittings in size NW50/QF50/KF50 and ISO50. This is a modular snap together approach to assembling any vacuum fittings systems.  Pumps connecting to just about any equipment.  Reusable.  Good for use with pumps and systems to 1x10-6 Torr.  Industry standard. Leak tight sealing.  User can be assured of maximum pump performance and less time chasing higher pressure issues causing systems to under perform.