Adjustable dumbbells are light weight training equipment where you can adjust the resistance (weight) by re-setting a mechanism, rather than switching plates or taking up another dumbbell. In contrast to fixed-weight dumbbells (5 lbs, 10 lbs, 20 lbs, etc.), adjustable dumbbells store multiple weights in one container. You just crank a dial, push a pin out, or turn a handle to select y... https://fitnessofhealth.com/how-do-adjustable-dumbbells-work/