This is a model of a quadror, a folding structure created by Dror. ( http://www.quadror.com/)

The sawhorse is just one of its incarnation. It is usually made from four L-shaped parts which are glued/screwed two by two. After assembly, the folded structure may be unfolded in the form of a sawhorse.

After printing, carefully separate the two parts with a utility knife.

Original model: https://www.thingiverse.com/thing:921314