The Fight Monkey Free Standing Pro Speed Bag is PVC covered. The punch ball is foam filled and has a diameter of 8.7" (22cm) and a height of 11.2" (28.5cm). The punch ball can be lowered to 50" and can be raised to a maximum of 63". The flexible coil spring is chrome plated to prevent rusting and is 9mm x 90mm. The base is made of plastic and should be filled with water or sand before use. When filled fully with water the base will weigh up to 135 lbs (60kg).