If you want to see the benefits of developing gear for ProTour cycling teams, look at the rear panels of the Giordana FormaRed Carbon Flex Bib Shorts. You'll notice that there's an extra spandex panel that runs from the bottom of the glutes to the bottom of the shorts on both the right and left leg. These panels first started appearing in the legs of US Postal team skinsuits, then Team Discovery clothing, and in 2011, you could see the red panels in the back of Team Radio Shack's black shorts. These are Xspansion Channels that, as the name suggests, expand to accommodate legs of all thicknesses, from skinny legs to moderate and, especially, thick gams. The Flex shorts are a bit longer than their FR-C brothers to better accommodate thickly-muscled legs.You might be wondering why you'd need more stretch. It's because these shorts use highly compressive spandex, known as HC-44, that doesn't merely stretch around your legs, but hugs them in a tight embrace. The material has 44 threads per centimeter, making the material very thin, light, and tight. Compression is part of the next wave of legal performance enhancements, with some evidence that it can help you go farther faster. Even if you're skeptical, the shorts keep the chamois in place like nobody's business. The 5cm-wide comfort cuffs feature Ametista material on the outside and Antigua on the inside to help with wicking and sticking. They're also great for holding knee- and leg-warmers in place.This sort of thinking is everywhere on these bottoms. Because the Ametista is interlaced with carbon thread, which has anti-bacterial and anti-static properties, it is used around the waist to protect your internal organs from electrical interference. The bibs are made with the thin Ametista fabric as well, and are cut with curves so they lie flat as they wrap around your torso. But they don't have Antigua backing like you'll find in FR-C and Laser bibs so they'll have more give. Micromesh sits between the bib straps in back to promote cooling ventilation. There are reflective tabs on the backs of the legs as well.These Flex bibs come with Giordana's top-of-the-line Cirro Omniform insert. It's a variable thickness (4-14mm) stretch pad, with a waffle top for comfort and wicking, and the microfiber's threads are infused with aloe vera for a little extra skin softness and protection. The Giordana FormaRed Carbon Flex Bib Shorts come in Black or Black with Red. Sizes run from Small to XX-Large.