Ultra-soft feel, realistic vagina design. Skin safe, with softer inner sleeve nubs for intense stimulation. Tighten or loosen end-cap to control suction for added sensation. Vibration added for stimulation. To use with vibration slide cover and insert "3" AAA batteries (not included) replace cover. Insert dc pin to bottom of cup. (Slide cover to locate pin hole). Press button to turn on and off. Tap and release top button to adjust vibration patterns.