[[File:PVI1.png|frame|center|Image reproduced from [https://commons.wikimedia.org/wiki/File:Passvib1.svg here]]]

It gives an indication of how much source vibration will be transmitted through the interface to the satellite. It is a relative measure given as a ratio of vibration at two points: one on the top of the isolator and one on the source. Here is an example of a transmissibility curve of negative stiffness isolation system with natural frequency 0.5Hz.

[[File:Transmissibility.png|frame|center]]

The transmissibility hovers around initially as the frequency of source reaches natural frequency, the amplitude rises catastrophically. We need dampers to damp this kind of vibration to ensures the structural stability and integrity of any payload.

====Types of PVI Systems ====

*[[Pneumatic or air isolators]]