Emergency Window - RailFans love it. Why? Go figure. - Anubharadwaj Maharshi

A good summary of the differences, just a few corrections.
1) There are no HLHB coaches with FIAT bogies. All coaches with LHB type stainless steel shell and FIAT bogies are referred to as LHB coaches (Both EOG type and self-generating). and all coaches with LHB style stainless steel shell and ICF bogies are referred to as Hybrid-LHB coaches.
2) Both HLHB and LHB coaches have CBC couplings.
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It is the use of ICF bogies that makes hybrid-LHB coaches different from LHB coaches. Self-generation is just a facility added to the coach, it is not a part of the coach's design or technology and is not a differentiation between LHB and HLHB.