I'm using my phone ... link has general info about "compact" models. I googled tr shotgun we have and they still come with 18".

It's a great gun for my small framed wife. Frankly, it is infinitely more useful inside the house for me as well. It's light, small, handy and plenty powerful. We keep ours loaded with a mix of shells (rural farm life defense is more likely to involve protecting chickens from coyotes and skunks than people from people...and we carry sidearms).