I must be looking in the wrong place, but it felt difficult to figure out what to use for remove Testor’s Black Enamel from a paint brush. After reading a few sources, we decided to use a small container (wire nut) filled with Paint Thinner.
After inserting the brush, covered in black enamel, into the wire but, five the brush a several spins, pull the brush out, and wipe the brush with a paper towel. Allow it air.
Good to go!