Why the New Apple Watch Might Not Be Any Thinner by Aaron Pressman @FortuneMagazine August 8, 2016, 9:20 AM EDT E-mail Tweet Facebook Linkedin Share icons One of Apple’s core design tenets in the mobile era has been thinner is almost always better. Whether it is the iPhone, the iPad, or the line up of iMac and Macbook computers, the consistent trend has been to make each product successively thinner than the model it has replaced. There have been exceptions over the years. The original iPhone released in 2007 connected only to relatively slow 2G cellular networks, not the fastest 3G networks of that time. A year later, Apple added the faster networking connection to the aptly named iPhone 3G. But the company didn’t want battery life to suffer from the power hungry technology, so it made the 3G slightly thicker than the original model. That history may help explain company’s rumored decision to keep the upcoming second-generation Apple Watch at the same thickness as the original model. According to a report by KGI Securities analyst Ming-Chi Kuo, Apple is planning to release two different updated versions of the watch later this year. One will be a minor upgrade closely resembling the original, inside and out. A second version will add a GPS chip and barometer sensor, allowing the device to track a user’s movements more accurately even without a nearby iPhone, a highly desired feature for runners, cyclists and other endurance athletes. Get Data Sheet, Fortune’s technology newsletter. But with the additional sensors, the watch will need a slightly larger battery. So even the higher-end new watch will be the same thickness as the original 2015 watch, Kou wrote. Next year, Apple aapl will add a mobile radio to the watch so it can connect to cellular networks on its own without a phone nearby. Thus, a major physical redesign won’t arrive until 2018, Kuo said. The original Apple Watch comes in two sizes, and both models are 10.5 millimeters thick—considerably more bulky than a typical wrist watch. For example, a popular Casio wrist watch sold on Amazon.com is only about 7.6 millimeters thick. KGI analyst Kuo, who is based in Taiwan, is thought to have reliable sources among Asian companies that supplier parts and services to Apple. Among his many correct predictions, he reported that last year’s iPhone would use a stronger aluminum to prevent bending and be made in a rose gold color option. In 2014, he accurately reported on updates coming for the iPhone, iPad, and iMac. Apple is expected to unveil new versions of the iPhone at an event next month and could show the new watch at that time as well. The tech giant could use a boost as iPhone sales declined in the first half of the year for the first time ever.