Download our flat bottom boat design for the extreme flats 20, a light weight, quiet hull with low freeboard. buy flats boat plans and more at bateau.com!. It takes only a little time, money, and effort to build one of these rugged – yet simple – flat bottom skiffs. every model includes details for two bottom profile shapes.. Why do i have register to get the free boat plans? basically i would like to know my visitors and have the opportunity to get in contact with you..