The very description as 'plastic' indicates that the materials are neither 'rigid' nor 'permanent' in the way that metals or ceramics are, and they therefore have to be treated accordingly. This description of the characteristics of ABS is clear enough.
Having long been acquainted with the snapdoodles of 8500/9500 cases, I have also seen the result of the degradation of the rubber (the B in ABS) component.
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