The finish grade. Where Surfacer 1000 is built to fill, 1200 is built to be smooth — a finer particle that lays down a tighter, flatter surface with less texture of its own. That matters most under gloss and metallic top coats, which magnify everything beneath them: a gloss red over a coarse base looks subtly grainy no matter how well you polish it, and metallics are worse. Under 1200, they lie down properly.

The neutral grey is the other half of the job. Grey is the colour that shows you what you've actually built — under raking light it picks out every surviving seam, sink mark and sanding scratch while there's still time to fix them, which white and clear primers simply can't do. It's also the honest all-purpose base, shifting your top coat colour less than a white ground and giving even coverage across mismatched plastic, putty and filled areas. At 170ml this is the value-size can, so there's enough for a full car body with the panels and interior.

• Fine 1200 grade — smoother base than 1000, ideal under gloss and metallics
• Grey shows up seams and surface flaws while they're still fixable
• Even, neutral ground over mixed plastic, putty and filled repairs
• Sands back beautifully, wet or dry, for a polished finish
• 170ml value-size can — 70% more than a standard 100ml spray

Tip: Because it's a fine grade, don't ask it to fill deep scratches — it won't, and piling it on to try just costs you detail. Do the filling properly first with sandpaper or a coarser surfacer, then lay 1200 over the top as your final base. That two-stage approach is how show-finish car bodies get done.

Understanding the numbers: Mr. Surfacer's grade is its coarseness. 500 is the heavy filler for gouges and bad seams. 1000 is the standard working grade for most builds. 1200 is finer — less filling, smoother finish, the choice under gloss and metallic paint. 1500 is the finishing grade where any texture at all would show. Lower number, more filling; higher number, smoother surface.

Which one do I need? Choose 1200 grey for a smooth, flaw-revealing base, especially under gloss finishes. Choose White Surfacer 1000 (B-511) when the plastic underneath is dark or multi-coloured, or when you need more filling power. If paint adhesion rather than surface quality is the problem — resin, photo-etch, bare metal — use Mr. Primer (B-512) underneath first.

Specifications

Brand: Mr. Hobby (GSI Creos / Gunze Sangyo)
Item No.: B-515
Type: Lacquer surfacer — filling primer, aerosol
Colour: Grey
Grade: 1200 (fine)
Volume: 170ml (value size)
Suitable for: Styrene, ABS, resin, putty and filled areas
Sandable: Yes — wet or dry
Use in: Well-ventilated area; wear a respirator