This 2 in 1 shampoo, Dynamic Duo in Gallon economical format because there is a concentration of 15 to 1 is what makes it economical. Dynamic Duo 2 in 1 Double K is a professional shampoo widely used by groomers because the 2 in 1 formula cleans and revitalizes while detangling in the same step. Dynamic Duo 2 in 1 Double K Shampoo can be used at home as well.