Describe:Adjustable rope length.The minimum inner diameter is about 16 cm.The maximum inner diameter is about 34 cm.The minimum waist circumference is about 49 cm.The maximum waist circumference is about 120 cm(with 24 tire links).Additional function: massage small pieces.Color: pinkThe ball weighs about 200 grams.The package includes:1 x Hula hoopThree times the efficient exercise hula hoop burnsfat three times faster than the traditional hula hoop.You can burn 800 calories in 30 minutes (5 times a week).Good-looking waist or thin legs, good-looking legs or slenderarms or tight buttocks, this is your good partner for weight loss.Smart counting: The correct guide rails and pulleys will not getstuck. Smart Counter can provide you with accurate training dataInnovative design: The anti-falling fitness ring is composedof 24 small knots. You can adjust the waist size accordingto your needs, easily fasten it, and let your family use thefitness hoop.Self-adjustable training level: The fitness hula hoop has asoft gravity ball. You can adjust the weight of the sand inthe ball or the length of the hula hoop according to yourtraining level. All you have to do is to rotate the hula hoopso that the ball slides along an inertial path. Please notethat this pulley attachment is only suitable for hula hoops,not for other items.5 minutes of training = 45 minutes of running: Hula hooptraining is an intensive and effective exercise. Hula hooprequires a lot of physical exercise, so you only need touse the hula hoop for 5 minutes to achieve the trainingeffect equivalent to running for 45-60 minutes. Regularexercise can improve your coordination and create apermanently attractive body shape. Your body will thank you.Smart hula hoop is easy to use: Compared with traditionalhula hoop, this smart hula hoop will not fall off.By putting the various chain links together, the diameterof the tire can be perfectly adjusted to your waist.Please note that due to manual measurement of waistcircumference, there may be a difference of 1-2 cm.This 24-link hula hoop is not suitable for people with awaist circumference of more than 120 cm.Please check your size carefully before buying