What do you recommend for a brush on insulator?

[alank2]

I've got a project that uses a CR2032 and the + is exposed.  For the - I've run a short trace to a very low PTC (10mA), but there is also a small microcontroller, resnet, and a TVS.  Is there a clear (and not ugly) type of liquid insulator I can brush on that won't be ugly?  Something that is cheap, easy to get/use?

[wraper]

There are Chinese RTV silicones for electronics which cost a few $ for a tube. There are several types with different properties with 701-708 model numbers. And they are actually pretty good. https://www.aliexpress.com/item/4000416228722.html?spm=a2g0s.9042311.0.0.51884c4dAa7hxC