Credit: Travel + Leisure Best Duffel Bag Deals 4K shoppers bought in the last month: Bagsmart Duffel Bag, $21 (originally $36) Water-resistant: Forestfish Duffel Bag, $24 Lots of pockets: Bagstellar Puffer Tote, $30 (originally $50) Shoe storage compartment: Oeihuivt Weekender Bag, $34 (originally $48) Sporty and functional: Beulptn Travel Duffel Bag, $20 (originally $27) Under $20: Seafew Duffel Bag, $16 (originally $23) A puffer bag may not be the first thing that comes to mind when you think of a reliable carry-on, but Bagsmart proved that’s possible thanks to its cute puffer duffel bag. More than 4,000 shoppers purchased it in the last month, and it’s on sale at Amazon today for just $21. Whether you’re gearing up for a spring weekend getaway and don’t want to check a bag, or you’re looking for a functional bag for the gym or work, a sleek duffel bag is our pick for all of the above.…