OPPO has confirmed that the upcoming K3 smartphone will be launched on May 23, 2019. This new mid-range device will apparently be equipped with VOOC 3.0, with a fresh range of accessories to match. They are said to include power banks with the same technology.
https://www.notebookcheck.net/The-OPPO-K3-may-be-joined-by-new-VOOC-3-0-accessories-on-its-launch.421144.0.html