Price 100$ on Unity Asset Store: https://assetstore.unity.com/packages/tools/truss-physics-41801
But now you can download Truss Physics FREE.
Truss Physics v1.0.2 Beta
Truss Physics is a high quality soft body simulation for a wide range of materials from jelly-like and springy to almost rigid but deformable.
+ Robust soft body simulation.
+ Breakable soft body constraints.
+ Interaction with rigid bodies.
+ Seamless Unity integration.
+ Tutorials and samples.
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