"Gash" in general have increased particles and a higher rate of pigment content which are the reason the paints can cause diffusion of reflection of light to increase the particle size.
The drawbacks are muddiness caused by color mixing.
"Poster Color" usually uses intermediate or below level pigments so a bright color can be actualized, but lightfastness and durability considerations are not that great.

"Gash" for fastness, "Poster Color" for brightness, 2 strong points gathered together to create an all new "Opaque Water Paint", which is the "MATCH Poster Color & Gash"

The 4 varieties; Basic, Bright, Rainbow, MATCH Color, when used on top of each other, the earlier colors can be seen below the later layers, but "Poster Color & Gash" when dried can completely hide the earlier color layers.

There is a difference in transparency and opaque but pigments used are the same ultrafine particle pigments used in "MATCH water paints" and the same characteristic of non-color saturation due to color mixing.

《 Precaution for Usage 》
*The paints when wet seem a bit transparent, but will become completely non-transparent when dried and colors in earlier layers will be completely hidden.
*Painting layers over before drying could cause the surface to smear and complete drying of paints before painting layers is recommended.
*Mixing of other products freely can be recommended.