Hampshire Marine Police Unit, along with explosives experts Ramora UK, will be holding their final flares amnesty on Sunday 4 October at the Royal Victoria Country Park near Netley.
They will be at the Solent Boat Jumble, for anyone with out of date flares to bring them along, have them checked and to dispose of them safely.
The service will be free of charge, although Ramora will be accepting donations for charity.
There will also be the rest of the Solent Boat Jumble to enjoy. Entry is £4 and is at the Royal Victoria Country Park, Netley, Southampton, SO31 5DR, just off Junction 8 of the M27.