These ground cache vials are used for more advanced truffle dog training. Put a small piece of truffle or a drop of truffle oil on a cotton bud or piece of kitchen towel inside the vial, and then push it into soft ground for your dog to then locate.
We recommend you initially mark the position of the ground cache vial with a small stick, stone or leaf so you can find them if the dog does not! As they are small (c. 4 cm long), try to avoid your dog getting them in its’ mouth. Offer offer the dog food in exchange for the vial if your dog does not drop on command.