This is a handy ticket which is valid all day on 99% of buses* in all parts of Kent. You can buy it from the driver on any Stagecoach or Arriva bus at £6.30 or £7.20 respectively. They accept each other's tickets. Please note: other day tickets are available but are not valid on other operators' services.
*see the 'bus information' under 'Kent Bus Maps' for each town to see which routes are run by other companies but are KCC-supported and so accept Explorer tickets.