Exclusively for Prime members, Amazon offers this Dog Food and Treats Sample Box bundled with an $11.99 Amazon Credit for $11.99 with free shipping. (The credit must be used towards purchases of similar dog food and treats.) Assuming you'll use the credit, that makes the sample box essentially free. Each box contains six or more samples from brands like Blue, Natural Balance, Cesar, and The Honest Kitchen.

Note: This item usually ships within 1 to 2 2 to 3 weeks.