I have a small selection of harnesses, leashes, treats, etc available for clients to purchase. I’m testing out using a shopping cart here:

Bark Pouches
$9.00

Larger 80 gram size, in 4 flavors. Can be stored at room temperature until opened, then refrigerate between uses. The packaging says that it should be used within 3 days, but I have had these easily last 2 weeks as long as I only took them out of the fridge for training sessions.