STERIS’ Vesta-Syde SQ 128 Ready to Use Quaternary Ammonium Disinfectant is the non-sterile version of our phosphate-free one-step cleaner and disinfectant formulated for use on hard, non-porous surfaces. Made with same main ingredients as the Vesta-Syde SQ Disinfectant concentrate, Vesta-Syde SQ RTU Disinfectants kill a broad spectrum of common bacteria and fungi. At a use-dilution rate of 0.8% v/v (1:128), Vesta-Syde SQ 128 Ready to Use Disinfectant requires no mixing or activation for convenient and consistent use.