Idk. It looks very dark and the sig is very thick.. I do not know if this could pass authentication. There is no definition to the sig. Everything is mushed. But it comes from a seller that I have done Quick Opinions on and came back Likely Genuine. Just very hard to say on this one.
very easy to say PASS. The only reason to buy a bat with Koufax on it is to smash it over your own head for being a moron... especially trash like this one.
As someone noted, the signature has no detail and is a sub par example at best. It is an example I would avoid simply because it could always be questioned, even if it is authentic.
I never really understood getting pitchers' signatures on bats, but maybe that is just me. :-)
I do not believe the slowly signed ,no slant signature is authentic anyway. I don't know that Koufax doesn't sign bats, he just doesn't sign a lot of anything.