Great black ink for the logos on your tennis strings. The ink adheres to the strings very good and you should wait at least an hour to assure the ink is dry.
Racquet Stencil Ink
black is great, white not quite
The black ink provides one coat coverage. White ink takes about three coats and some additional spot touch ups to look good. Super happy with the black, less so with the white, but maybe it's just the nature of the white ink on dark coloured strings...