4ZA Stratos Alloy MTB Riserbar 6061 double butted aluminum 680 wide x 15 rise x 9 deg sweep Available in Black/white or Black/Red Bar Diameter of 31.8 Oversized clamp area Multiple color options to match any bike design Butted and tapered 6061 alloy for increased strength and durability Oversized clamp area Bar Diameter: 31.8 mm