Thunderbolt 3 combines ultra-high bandwidth with the ultra-versatility of the USB-C industry standard to create one revved-up universal port. And with up to four ports, you can charge, transfer data or output video from either side of your MacBook Pro.
Testing conducted by Apple in April 2019 using pre-production 2.8GHz quad-core Intel Core i7–based 13-inch MacBook Pro systems with 16GB of RAM, and pre-production 2.4GHz 8-core Intel Core i9–based 15-inch MacBook Pro systems with 32GB of RAM; and shipping 3.5GHz dual-core Intel Core i7–based 13-inch MacBook Pro systems, as well as shipping 3.1GHz quad-core Intel Core i7–based 15-inch MacBook Pro systems, both configured with 16GB of RAM. Tested using Mathematica v11.3.0 with built-in benchmark, WolframMark. Performance tests are conducted using specific computer systems and reflect the approximate performance of MacBook Pro.
Testing conducted by Apple in April 2019 using pre-production 2.4GHz quad-core Intel Core i5–based 13-inch MacBook Pro systems with 8GB of RAM and 512GB SSD. The wireless web test measures battery life by wirelessly browsing 25 popular websites with display brightness set to 12 clicks from bottom or 75%. The iTunes film playback test measures battery life by playing back HD 1080p content with display brightness set to 12 clicks from bottom or 75%. The standby test measures battery life by allowing a system, connected to a wireless network and signed in to an iCloud account, to enter standby mode with Safari and Mail applications launched and all system settings left at default. Battery life varies by use and configuration. See http://apple.com/uk/batteries for more information.