LESIR Water Bag, Adjustable from 10L (10kg) to 35L (35kg) 【Includes a Manual Supervised by Basketball Corporate League Players!】 Core Training, Foldable 【Water Bag with Manual Supervised by Corporate Basketball Players!】 This water bag comes with a manual supervised by basketball players from a corporate league. If you're new to training and don't know where to start, this training manual is perfect for you. It's not just any manual; it's a manual supervised by basketball players from a corporate league, packed with efficient muscle training suitable for the areas you want to strengthen, featuring an "A2 poster" and "videos"! 【What is a Water Bag?】 A water bag is a training tool that uses water. As the water flows, the water inside moves, making it ideal for core training! The weight can be adjusted, so it can be used by beginners to advanced users. Therefore, it's also great for muscle training for children in club activities. 【Visible Weight with Markers!】 Comes with markers for easy reference! You can increase the water as you train, allowing you to check the weight and feel your progress! 【Supports up to 35L!】 Supports up to 35L! If you want to add more water than the markers and do more serious muscle training... This solves that problem! You can fill it with up to 35L of water, so you can make it even heavier to suit your muscle training! 【Foldable for Storage!】 When not in use, you can drain the water and air, and fold it for storage! It can be folded up small, so you can take it out only when you need it! Even if you don't know how to drain the water and air, it comes with a manual, so you can easily store it.