ADJUSTABLE WEIGHT VEST: This one-size-fits-most exercise vest by Zelus weighs in at 4 pounds by itself but reaches up to 10 thanks to the included six 1 pound iron sand weight bags, allowing variable low impact resistance that strengthens your core and endurance no matter your exercise routine ADJUSTABLE ERGONOMIC DESIGN: Our weighted vest evenly distributes its load even during intense workouts, with its hook-and-loop fasteners offering a snug fit for teens or adults DURABLE & COMFORTABLE: Our soft neoprene material gives you long-lasting comfort combined with long-lasting use, able to handle everything from yoga positions to kickboxing, light jogging to intense cycling HELPFUL & SAFE: Bring along your keys, wallet, or smartphone in the wide pocket so they don't bang against your legs as you exercise; even while out and about, you'll stay safe and easy to see thanks to the high-visibility reflective strips on the front, shoulders, and back Prompt Response: Zelus's adjustable weighted vest comes with our friendly 24/7 customer service; try it at no risk and blow through any plateau with ease.