Adjustable Dumbbell: Fun, adjustable and colorful dumbbell set, suitable for children! : The perfect way to exercise child slowly. Both children and adults can use it. Add this to your kid's family gym! Fill Sand/Water: Can be filled with sand or water to increase weight. Improve Motor Skills: Dumbbells are perfect for kids to increase their strength and improve their motor skills. Colour:Gray+green+pink+blue+red Material:plastic Size:Stick: 36cm Stick diameter: 3cm disc: 400ml,250ml,150ml Package Contents: 1 x Gray stick 2 x Green disc 2 x Pink disc 2 x Blue disc 2 x Red screw buckle Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.