Dirigo XT 140 kids seat?

In the description it mentions a removable kids seat. I’ve seen the kayak in person and see the black thing mounted near the cup holder. How Exaclty is that aids seat? Or is it a mount for a seat you have to buy?

Kids Seat
It is basically a hard piece of plastic that allows a small 2- to 4-year-old to sit on. They sit on the flat portion with their legs on the sides of the seat facing forward. Necky makes a similar seat for the Manitou II tandem and Old Town with the Dirigo tandem. It doesn’t look very comfortable, but it has been a long time since I was four.