GNZ-B515 (Ref. code)
GUNZE SURFACERS act as Primers and fillers, It has 4 grades, Lower the number thicker it is, higher the number, more detailed focused. The #500 tends to be used in the first layers, to fill the scratches and big gaps while #1000 - #1200 - #1500 are used as primers. it can be used in first layer or later depending modellers technique and model kit.
Surfacers can be acquired Spray or bottle. There are different colors, that has different purpose, white to get a shinner color, black for candy / metal colors, grey to find misstakes or to use as basecoat.
Grades 1000-1200-1500 used with airbrush it is recomended to use a ratio of 1:3 (1ml surfacer 3ml thinner) and the thinner to be used is GNZ-T102 110ml and GNZ-T103 250ml. Gunze Surfacers are widely used and are considered by many modellers as the best "primer".