This is a Navigation Toolbar Top 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 "navigation toolbar top" icon consists of a rectangle. Three quarters of it extends from the lower portion upward. The third quarter has a line crossing horizontally. In the upper quarter are two small circles next to each other horizontally positioned to the left. To the left of the upper quarter is a small thin rectangle. It looks like a rectangle with two round buttons on top on the upper left and a long, rectangular horizontal on the upper right, with a dividing line underneath them.