A manual vent valve that lets air into a vacuum vessel to bring it back to atmospheric pressure. It opens fully in 2 turns of the knob and vents a 50 L vessel in 14 seconds. Flange sizes from KF10 to KF40 are available.
| Model | KF10VVM, KF16VVM, KF25VVM, KF40VVM |
| End Connection | KF10, KF16, KF25, KF40 flange |
| Operation | Manual (fully open in 2 turns) |
| Venting Time | 14 s (50 L) |
| Pressure Range | 1×10⁻⁸ to 1000 mbar |
| Leak Rate | 1×10⁻⁹ mbar·l/s |
| Material | Body and plate SS304, washer PTFE, O-ring FKM, screw cap aluminum |
| Mounting Orientation | Any |
| Weight | 0.1 kg |