If you are on a budget, this Free People Tank will fit the bill. It's a fail-safe choice, while not very expensive. In this price range, you can also check out this Hinge Tank. It's also a popular item and won't break the bank. You may also want to look at this James Perse Tank. This item is not expensive either, but it will make a difference in your wardrobe.
If you're looking for an item in the middle of the price range, check out this Ella Moss Tank. While the price is very reasonable, this product is an easy wardrobe update. It's also worth looking at this Forte Forte Tank. This piece is extremely popular and, just as importantly, not very expensive. Alternatively, opting for this Twin-Set Tank is a good choice as well!
If you're not a thrifty type, then what you're looking for is this Maison Margiela Tank. It's more expensive but worth your money. Another product we're drooling over is this Adam Lippes Tank. It's expensive but you get what you pay for. And one more item you might be interested in is this Theory Tank. 'Cause you deserve nothing but all the finer things!