This is a Watch icon. We've made it in iOS style, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 12,600 icons, all in the same style and quality.
This is a picture of just the face of a watch. It has a small arm which shows you the minute, and a larger one which shows you the hour. It seems to be pointing towards 5:10, although there are no numbers pictured.