Thanks to its unique dual motor design, the F1s Red combines conventional vibrations with a totally new sensation never before experienced in a male pleasure product: SenSonic technology. It is the same high-tech concept that made LELO SONA the best-selling sex toy in the world of all time. Instead of standard vibrations, one of the engines emits powerful sonic waves that penetrate deep into the penis, making it feel as if it is resonant pleasingly from all directions at once, instead of simply