Portable drawing board / Stationery

When we go out to paint, we will encounter the inconvenience of carrying drawing board,carrying format A3 size the small drawing board going by car may also reluctantly, but how bring format A2 size or format A1 size drawing board in car? so I have designed this portable drawing board, its principle inspiration originates is from the oil painting frame and oil canvas, like oil canvas it is a plastic kneading board ,it was tightened on the foldable frame outer edge, then fixes by the lock catch on the outer frame edge, like this might paint pictures above the drawing board.