The Oakley Fast Jacket comes in two styles. The XL is the one with the larger lenses. As with the Fast Jacket, you're getting Oakley's latest advance, the Switchlock, applied to open edge lens architecture. You get the benefits of their race-specific Jawbone in a style that is technical enough to be worn during hard riding and casual enough to hang out at the beach.
Looking at the Fast Jackets, you notice the stainless steel Switchlock. Put a pair in your hands, you can feel how light and balanced they are. Put them on and look into the distance, then down at your watch, then over to the corner, and you'll see the benefits of having pinch-free lens mounting. Like the Jawbone, the Fast Jacket has a hinge, Switchlock technology they call it, that locks the lenses into place. This means that it's easy to change lenses, and there is absolutely no distortion whatsoever, taking Oakley's famed XYZ Optics up another notch.
The Switchlock is easy. Open it up, the lens drops out. Insert the lens, lock the stainless steel Switchlock lever, and the lens is firmly in place. Aesthetically, the finished stainless adds nice visual pop to the already attractive package. The XL in the name means the lenses are larger, with more coverage than the Fast Jacket.
The Oakley Fast Jacket XL comes in three colors, and each comes with two sets of lenses. One is for sunny days, the other for overcast. The Chrome FMJ (Full Metal Jacket) comes with Blue Iridium and Jade Iridium lenses. The Lemon Peel comes with Fire Iridium and Persimmon lenses. The Polished Black comes with Black Iridium and Persimmon lenses. The lenses come packaged in a soft vault (aka hard case). Finally, the glasses also come with two sets of nosepieces to best customize fit.