Zipp: When it comes to handlebars, tried and true aluminum remains the material of choice for many pros. In part, that s because their bikes have to meet a minimum weight requirement. But that means aluminum bars such as the Service Course SL have to meet the fit, durability and performance standards of teams such as Team Exergy TWENTY12 and Cannondale.The Service Course SL is produced using Zipp's proprietary ZTL-71 alloy and intricate internal butting processes to achieve a weight of 285 g (44 cm) with superior strength and rigidity. It features a classic look with round cross-sections throughout and is available in the same comfortable Short & Shallow or Traditional Bend shapes as our carbon bars. What's more, the drops are angled outward by 2 degrees to reduce wrist strain.