The blue one has a squeeze clamp that will fit almost any handle even the back end of your broom stick,
I got slapped when I told Helen it was a finger nail brush attachment for her to do her nails when she was out riding on her broom!!!!
the white one takes a threaded handle.
I have found the blue one to wear faster, Both work, White one seams to work better on the real dirty stuff, guess cause it is more aggressive like Larry said..