Ferro harnesses the power of vibration and metal. This stainless steel rechargeable bullet has 6 strong vibration patterns for you to choose from. Low, medium, high, slow pulse, fast pulse and escalating. Simply push the button at the base to scroll through the vast choice easily and effectively. This bullet is 100% waterproof so you can take advantage of the the stainless steel by running it under hot or cold water for temperature play or simply take it to the bath of shower to experience the combined sensation of metal and water. Ferro is rechargeable so there's no need for batteries. Simply unscrew the base and attach the magnetic USB charging pad to the points on the toy. *The Nexus Stainless Steel 6 speed Bullet can be used with the Nexus Vibro. Insertable Length 2.5 inches Shaft Width 0.6 inches