What size are the spark plugs on a Peugeot 206?

The spark plugs for a Peugeot 206 typically have a thread size of 14mm and a hex size of 21mm. The specific type of spark plug may vary depending on the engine variant, but common options include NGK BKR6E and Bosch FR78X. It's always best to consult the owner's manual or a parts catalog for the exact specifications for your particular engine model.