Aleo is a well designed, modern slab serif font that you can download for free. It has 3 weights together with true italic companion. According to the font designer, Alessio Laiso, he designed this font as the slab serif companion to the Lato font by Łukasz Dziedzic.
Styles: 6 (3 weights + italics)
Designer: Alessio Laiso
Commercial use: OK
Web font included
SIL Open Font License