You would need the cr38 brush set:
There are three types of brush,
Truvox Cimex Cyclone Shampoo Brushes (WHITE) (38cm) 11-1607-0500 (which are the ones you have)
Truvox Cimex Cyclone Standard Scrub Nylon (WHITE) (38cm) 11-1605-0500 (stiffer nylon brush)
Truvox Cimex Cyclone Medium Scrub Polyprop (YELLOW) (38cm)11-1604-0500 (really stiff)
(
all listed here )
In addition there are drive pad holders and wire brushes in various grades
Also see
this useful post