Spigen Rugged Armor ($12)
If you're looking for a great overall case that's thin, durable, and affordable, this is it. The Spigen Rugged Armor is by far the most popular TPU case on the market. So much, in fact, that multiple other companies copy the design. This is the original.
The Spigen Rugged Armor has a thin profile and is all TPU. They've added a few extra layers on the corners for additional drop protection, glossy accents on the sides, and a nice carbon fiber finish to the top and bottom. Every Spigen case is cut to perfection, has easy to press buttons, and are typically some of the best Galaxy cases on the market.
If you're looking for a good, typical, thin TPU case with no frills, check this out.