Description: [Dumbbells rod]: Inside is a rigid steel tube, wrapped with high quality pp on the outside to reduce pressure and slip. [Durable]: Hexagonal PVC plastic nut with deepened thread design, prevent weight plates from sliding off during the exercise. Threaded ends with lock collars provide a safe, secure workout. [Feature]: Precision thread Dumbbell Handle, due to their size and versatility, adjustable dumbbell bar can be used to create a variety of movement patterns to movement specific strength. [Great choice]: Dumbbell is ideal for various warm ups sports and strength workouts like arms, shoulder, abdominal, legs or back training. [Function]: Make your dumbbell to barbell. Great replaces for your old dumbbell rod, effectively improve your strength training.Great for household fitness device use. Specification: Material: Steel, PVC Size Chart: 35cm/13.78inch 47cm/18.50inch 55cm/21.65inch Package Includes: 2 Piece Dumbbell Bars 4 Piece Nuts Note: Please allow slightly errors due to manual measurement and different monitors.