Agilent Technologies TwisTorr 305-IC Mode D'emploi page 259

To install the vent valve, unscrew the threaded plug (see figure below).
Figure 39
Then screw the vent valve into the pump and tighten it using a 16 mm hexagonal
spanner with a torque of 2.5 Nm.
Figure 40
TwisTorr 305-IC User Manual / 87-901-058-01
Technical Information
Vent Accessories
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