Toning up with bulky cast-iron weights could be a thing of the past with the invention of "magnetic" dumbbells.
The sleek and innovative O2 Magnetic Dumbbells consist solely of two electro-magnetic rings worn above and below the elbow.
Polarity and attraction/repulsion between the two can be varied meaning wide range of traditional exercises including curls, rows, pullovers and presses can be achieved.
The makers - Suhyun Yoo, Hongseok Kim and Juhyeon Lee - claim the resistance can be set at intervals of 3kg up to a maximum of 24kg.
The device can even track your workouts and when not in use are easily transportable - far more than 24kg of iron.