Origin-8's Fix8 Stem is a nice upgrade for your super-cool fixed-gear bike and perfect for mountain bikes, too. It's forged from lightweight and durable aluminum and features a 4-bolt face clamp that holds fast and makes bar installation/removal quick and easy. Plus, the opposing steerer clamp bolts apply more even holding force to keep your bars from changing position. At 50mm long, this stout stem is great for flatland tricks, bar spins, and anything else you come up with.