Tamiya Liquid Surface Primer 87075
Like the white variant this bottled brush-on primer is excellent for when you don’t want to deal with putty. It’s basically putty mixed with lacquer thinner at a certain ratio, and I’m sure you can make a mix yourself, but it’s more convenient to use this. Like the actual putty and spray-can primer, this sands well. Nothing gets scraped and the layers don’t get annihilated by one stroke. Definitely, use this if you want a brush on primer or something that can apply tiny amounts of putty.