Back Door Entry with this whisper quiet motor delivers mind blowing vibrations directly to your most sensitive spot. With one solid click of the button, you will go from flutter to a throb in seconds. Ultra hygienic silicone, hypoallergenic, firm yet super flexible and an easy grip. Easy cleanup, waterproof. Vibrating butt plug requires 1 AA battery, not included. Length is 5.75 inches, 4 inches insertable. Diameter ranges between 0.875 inch and 0.375 inch.