Delicious butt plug with internal steel balls Pine is a butt plug with a smooth and soft surface, made of silicone, to provide an easy and comfortable insertion. Pine is equipped with a steel ball inside, which when used gives a massaging sensation inside. We recommend that Pine is used with a water-based lubricant. Remember that it is a good idea to warm up before penetration, for example with your finger or by massaging with the tip of the Pine on the outside. - Waterproof - 100% medical silicone surface