Adjustable Speed Sled Sack Trainer 10 30lbs for Sprinters Agility Training Indoor Outdoor Size: 30*14*57cm Sandbag Sled Trainer: It can help trainer sprinters, football players, and other athletes strengthen lower-body to improve speed and explosiveness, leg strength and endurance Durable & Damp-Proof: Made of thickened PVC material, Surface waterproof and moisture-proof, both the sled and weight bags are constructed to handle drags and quick changes in direction, outside and inside, for all your training needs! Weight Adjustable: It comes with three removable weight bags, and each one is able to fill with 10 pounds of sand, these bags DO NOT come with sand/pre-weighted, so you can fill into 10-30lbs to meet your workouts. Multiple directions train: Can be trained in multiple directions to improve strength and mobility in any direction, more freedom when exercising. The size of the waistband can be adjusted, waistband lining is comfortable, soft and breathable,suitable for exercisers of different body types MULTI PURPOSE: MIMIGO Weight Sleds will allow you to intensify sprinting drills and make them way more interesting! Add hills, changes in direction, rows, drags, and more to your Sled workouts to reap the full-body workout benefits from this versatile piece of equipment!