This is the dumbbells which can boost your arm muscles and beautify your shoulder lines for a perfect and healthy body. You can also use a connecting option to combine two barbells into a barbell. Durable weight plates are made of hdpe and concrete for a good fitness experience. The dumbbell rod is made of electroplated hollow iron tube and has the characteristics of rust prevention and wear resistance. The handle ensures a comfortable grip and prevents slipping. And compact design does not take up too much space and is suitable for family members. It is your wise choice. Don't hesitate to buy it! The weight of the dumbbells can be adjusted to meet your different needs You can use the connecting nut to switch the barbell and dumbbell The exterior of the weight plate is made of hdpe and the interior is made of concrete Dumbbell bar with electroplating process is not easy to rust Ergonomically designed handle for a comfortable grip during exercise 4 threaded collars fix the dumbbell firmly to ensure that it does not shake or fall Dumbbells can be stored in the corners of the house without taking up too much space The dumbbell set weighs a total of 66 pounds and is suitable for home and office use Specifications Color: Black Material: Hdpe, concrete, iron pipe Dumbbell size: 19.5" x 8" x 8" (L x W x H) Barbell size: 39.5" x 8" x 8" L x W x H) Net weight: 70 lbs Package includes: 8 x 5.5 lbs weight plate 8 x 2.75 lbs weight plate 2 x Dumbbell bar 4 x Lock collar 1 x Connecting nut 1 x User's manual