20 volume

Wella Color Perfect 20 Volume Liquid Developer is used for standard formulations and provides up to 2 levels of lift and coverage of gray/white hair.

30 Volume

Wella Color Perfect 30 Volume Creme Developer is used for standard formulations and provides up to 3 levels of lift and coverage of gray/white hair.

40 Volume

Wella Color Perfect 40 Volume Creme Developer is used when extra lightening is desired and can provide 4 to 5 levels of lift.