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. Requires 1 AA battery, not included. Length is 4.25 inches, 3.5 inches insertable. Diameter ranges between 0.75 inch to 1.13 inches.