Bontrager's aluminum Lowriser bar is a great handlebar. It's simple, it's inexpensive and it gets the job done. It's 690mm wide, wide enough for extra control and leverage, but not so wide that you'll clip your bars on every tree. The 25mm rise is just high enough for confidence on descents, but low enough for those that like a racy position. And the 9-degree bend is ergonomically perfect for your wrists.
Clamp diameter: 31.8mm
Weight: 300 grams