These innovative fitness free weights by 7 nepo take inspiration from an unlikely, surprising source – Matryoshka Russian nesting dolls! Like the doll-in-doll system, additional weight can be added by nesting the weights together. With a quick snap-in/snap-out mechanism, you can transition from light to heavy in seconds to accommodate your workout routine without interruption. When you’re finished lifting and want to squeeze in some cardio, the handles double as a jump rope by connecting an included cord. Better yet, they make a cute desktop trinket when you’re not using them!