What are different berth types — LB, UB, MB, SL, SU?

LB = Lower Berth, MB = Middle Berth, UB = Upper Berth (in main bays); SL = Side Lower, SU = Side Upper (along the corridor). Lower berths are popular for elderly passengers; side berths are slightly narrower.

Each sleeper / AC coach has bays of 6 berths plus 2 side berths along the corridor.

Main bay (3 + 3):

LB Lower Berth — bottom
MB Middle Berth — folds down at night
UB Upper Berth — top

Side berths (along corridor):

SL Side Lower — bottom
SU Side Upper — top

Preference tips:

Elderly / pregnant: choose Lower
Light sleepers: avoid Middle (folds down at night, less headroom during day)
Privacy: Upper is best (no daytime traffic)
Side berths are narrower than main berths.

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