TATA Steel Express - Second Sitting sasta bhi, sabse achha bhi - Ravi Raj

All ICF coaches are anti-telescopic. They have crumple zones at the toilet areas which prevents them from being crushed length-wise in head-on collisions.
However, screw-couplings are not 'anti-climbing', which means that when a train derails or has a collision, the coaches can 'climb' over each other. Now even though the ICF coaches are anti-telescopic, this feature is useless when the coaches climb over each other. The 'anti-telescopic' properties are only useful when the coaches stay in order without randomly climbing on other coaches. The screw coupling is the reason why ICF coach accidents have higher casualties.
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CBC couplings provide the 'anti-climbing' feature, so that coaches tend to stay in a straight line, or reasonably well-oriented when derailed. Because of this the casualties are less. For example you can check online for details on the accidents of the Kaveri express (hit a boulder and derailed) and Coromandel express (happened a few years ago). Both trains had ICF coaches and were running at good speeds, but there were no casualties as they had CBC rakes.
One can see stripes at the end of ICF unreserved coaches like in the attached pic (pic 2). These indicate that the coach has an anti-telescopic design. Similarly, for SL/AC coaches, the yellow stripe indicator is painted at the bottom left corner on one of the faces of the coach (as in pic 1,3,4).
Credits: Pic 1 (Unknown - Google search, broken link)
Pic 2 - Trip Advisor (click here
Pic 3 - Samit Roychoudhury, IRFCA - click here
Pic 4 -Pavan Kumar, IRFCA - click here
I have highlighted the stripe markings in red boxes. These markings indicate that the coaches are anti-telescopic.