Hign vacuum manifold systems feature Easy Action PTFE stopcock valves providing for greaseless operation. Double-tube codes -50 & -54 feature Ace-Threds and 8mm OD tube-end ports. Double tube code -52 features hose barbed connections and 45 degree port placement. Walters manifold, code -40, incorporates a removable vacuum trap and Ace-Thred port connections.