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: 3cmdisc: 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.