ok. ive decided to go for pepper spray.
it seems powerful enough to take down 2 - 3 people for at least
half an hour.
Wikipedia
"The effects of pepper spray are far more severe, including
temporary blindness which last from 15-30 minutes, a burning
sensation of the skin which last from 45 to 60 minutes, upper body
spasms which force a person to bend forward and uncontrollable
coughing making it difficult to breathe or speak for between 3 to
15 minutes."
