Google is inviting existing Glass owners to swap their existing head-mounted display for a free updated version. While the new version of Google Glass looks identical, Google says it has made it “a bit faster and more durable.” Importantly, it’s also compatible with upcoming prescription frames for the device, and is designed for new accessories including the new shades and a mono earbud that’s included with the updated version. The wearable device isn’t expected to launch for consumers until early next year, but developers who joined the Explorer program have been invited to switch to the latest Google Glass version. Google unveiled the new version of Glass on October 28th, and Explorers who purchased a unit prior to that are eligible for the free swap.