POSTAL ABBREVIATIONS    

56 APO	1st CBPO
99 APO	2nd CBPO
APO	Army Post Office
APPU	Asian Pacific Postal Union
AMPC	Automatic Mail Processing Centre
CBPO	Centrally Based Post office
CPMG	Chief Postmaster General
CO	Circle Office
CSD	Circle Stamps Depot
CRC	Computerized Registration Centre
ECS	Electronic Clearance Service
EFT	Electronic Fund Transfer
eMO	electronic Money Order
ePOST	electronic Post
ESMO	Electronic Satellite Money Order
eVPP	electronic Value Payable Parcel
EMS	Express Mail Service
EPP	Express Parcel Post
FPO	Field Post Office
GPO	General Post Office
HPO	Head Post Office
ISP	India Security Press (Nasik)
IVP	Indira Vikas Patra
ILC	Inland Letter Card
IMO	Instant Money Order
IFSMO	International Financial System Money Order
IMT	International Money Transfer
KVP	Kisan Vikas Patra
MSY	Mahila Samridhi Yojana
MO	Money Order
MDG	Mukhya Dak Ghar
NSC	National Savings Certificate
PRSS	Pay Roll Savings Scheme
PIN	Postal Index Number
PLI	Postal Life Insurance
PSD	Postal Stores Depot
PTC	Postal Training Centre
PMG	Postmaster General
PCO	Public Call Office
PPF	Public Provident Fund
RMS	Railway Mail Service
RO	Regional Office
RL	Registered Letter
RLO	Returned Letter Office
RPLI	Rural Postal Life Insurance
SBCO	Savings Bank Control Organisation
SPA	Speed Post Article
SRO	Sub Record Office/ Sub Record Officer
TMO	Telegraphic Money Order
UPU	Universal Postal Union
VPL	Value Payable Letter
VPP	Value Payable Parcel
V-SAT	Very-Small Aperture Terminal

Thanks to : http://manooss.blogspot.in