This is a SLR Large Lens 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 12,700 icons, all in the same style and quality.
It's a logo for an SLR large lens and has a top-down picture of a camera with a large lens. There is a shutter button of the right side of the camera and a large lens made up of rectangles coming out of the top of the image.