Choito / Choito Umbrella-Specific Magnet Strap Greige Brand new, unused. The following is from the website: <Product Details> [Body] Diameter: 35mm, Thickness: 5mm [Material] PVC + Neodymium Magnet [Strap] 65mm [Overall] 100mm (length of body + strap) [Weight] Approximately 18g <Important Notes> * The magnet will react and attach if you bring the product close to the ceiling of a car. * Please refrain from using this on windy days as it is very dangerous. * Since you will be placing the umbrella on top of the car, there is a possibility that the tip of the umbrella may scratch the car. Please be aware of this and consider using a protective cover on the tip of the umbrella before purchasing.