Having done this myself, I know for certain that you get:
a. No gratuity
b. A limited resettlemment allowance according to your service - not much for an SSC
c. GRT ( Graduated Resettlement Time ) according to your length of service - not much for an SSC
d. ECDL Credits - standard amount, around 2.5 grand as I remember
e. A small pension payable from the age of 60 onwards... I did a 3 year SSC and will get Â£1000 pa.