Too high quality wiper motor brushes They fit 1959 1960 1961 1962 1963 1964 GM Cars with two speed wiper motor
 Corvette 1963 1964 1965 1966  1967.
 
Brushes are 1/4 x 1/4 x .450    6.3mm x 6.3mm 12.7mm lead. 
They are high dense carbon brush with a heavy lead, They are not repurposed electric drill brushes or grinder brushes, or a generic brush that's been sanded down to fit,  in my opinion The Grinder and electric drill brushes are too soft for a wiper motor application.