Lockable Gas spring of M/ s Stabilus, Germany, ( Model:- BLOC- O- LIFT ) to spec. No. KN00000. 0002 or M/ s Samhongsa, Korea, ( Model:- Lock Type- SG5050L05005 ) to spec. No. SHS- 110231 or Equivalent ( For seat reclining arrgt. of LHB Chair Car coaches ).