US Patent 10377406 Twice-foldable stroller

A twice-foldable stroller including a frame main body which is configured to have right and left front-angle frames to support front wheels and a horizontal frame connected at a lower part between the right and left front-angle frames, right and left rear-angle frames to support rear wheels and connecting frames connected between the right and left rear-angle frames and the right and left front-angle frames, and vertical frames connected to the right and left connecting frames; seat frames; backrest frames; support frames; extension frames; canopy frames rotatably connected to the extension frames; and handles, each connected to the extension frames, wherein right and left central portions are rotatably connected to each other.