Another use for net measuring tool

[Grrrrller87]

not secret, and not mine, but I use it. When I check the balls before a match, I try to mark each with the same kind of ink marking. It needs to be small, so that the ball doesn't become a mess by year end..... then if the ball gets tossed in with some other balls, or rolls to another court and someone starts practice serving it, we can identify this as one of the game balls without having to re-test it.

I typically try to fill in an 'e'. 'o'. or 'a' in the writing around the stem, just so I know which one.