Sigma Ultra Wide zoom. Designed for crop sensor, it’s an effective 12-24mm on a Sony such as I’ve used it (Sony A7 series in 1.5 mode using EOS to Sony E adapter). Canon EOS mount lens in good condition. Performs well in the time I’ve used it, especially the extreme wide end at 8 which is 12-13mm equivalent of full frame, far wider than a typical 16-17mm wide end of ultrawide zooms. Not fisheye or even barrel distorted, lines are remarkably straight. I would usually add barrel distortion in post to make the middle of the image stand out more.

It’s quite a heavy lens and the bulge front element design means you can’t readily add filters to the built in petal shaped lens hood. I don’t know where the ‘cap’ for it is, I usually didn’t use it since the built in hood protects from most common bumps or scrapes.

Worth looking up online to see the kinds of photos it can take at widest setting, it’s very attention getting and can be a big quality step up from ultrawide shots we’re used to seeing on GoPros and phones. Great for video too.