Gaianotes NAZCA Series - NP001 Mechanical Surfacer Heavy

Mecha surfacer = mechanical surfacer is a reproduction of the surfacer that NAOKI usually mixes and uses when making prototypes and models, and has a lineup of two colors. Since it is blended in a darker color than a normal surfacer, it can be used not only as a surfacer's main purpose of "making a base", but also as a "color" for internal mechanisms, frames and weapons.
Normally, two layers of paint film (surfacer → paint) can be done with one layer, so it reduces rubbing / peeling of moving parts and shortens the work.