PSA uses 42-inch screens to advertise your product or service, which means you get a 42-inch, crystal clear, full colour and moving advertisement. Unlike the newspapers which only gives you a once-off advertisement, PSA guarantees showing your advertisement for a minimum of 50 times a day , approximately every 8 to 10 minutes—i.e. 150 times per month (at a number of popular venues). PSA is the lower-cost advertising option!